Data storage medium, and apparatus and method of reproducing the data from the same

ABSTRACT

A data storage medium having stored thereon includes an audio sequence including at least one audio stream; at least one video stream; and reproduction control information for controlling reproduction of the at least one audio stream and the at least one video stream. The reproduction control information includes reproduction order information defining the order of at least one video stream, among the at least one video stream stored on the data storage medium, which is to be reproduced in synchronization with the audio sequence.

This is a continuation of application Ser. No. 09/266,313 filed Mar. 11,1999.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a data storage medium having stillpicture data and audio data stored thereon, and an apparatus and methodfor reproducing the still picture data along with high quality audiodata.

2. Description of the Related Art

Conventionally known optical disks which music information includingaudio data or moving picture information is recorded to and reproducedfrom include compact disks (CDs) and laser disks (LDs). Compact diskrecording and reproduction apparatuses and laser disk recording andreproduction apparatuses are conventionally known apparatuses forrecording and reproducing the above-mentioned information.

A CD is an optical disk having a diameter of 12 cm for storing musicinformation digitally recorded using an encoding technology referred toas linear PCM. CDs have been utilized as a medium for storing data formusic applications. An LD is an optical disk having a diameter of 30 cmfor storing moving picture information with audio data recorded as ananalog signal. LDs have been utilized as a medium for storing data forvideo applications such as movies.

Recently, optical disks having a diameter of about 12 cm for storingmusic information and moving picture information including audio datadigitally recorded. On such optical disks, either one or both of themusic information and moving picture information are efficientlyrecorded in the state of being digitally compressed in order to acquirelonger recording times and higher quality. Some of such optical diskshave a file structure which facilitates data exchange with computers andcommunication apparatuses.

In order to meet demands for mediums having higher quality recording andreproduction of audio information than CDs, the DVD-Video technology hasbeen developed and put into practice for realizing high quality audiodata reproduction of linear PCM, 96 kHz and 24-bit sampling. However,the DVD-Video standards cannot provide high quality linear PCMmulti-surround audio data reproduction or higher quality audio datareproduction. Accordingly, a higher quality technology has been indemand. However, the amount of high quality audio data is quite largeand thus the reproduction speed of data required is quite high. Thus, itis difficult to record and reproduce image data along with the highquality audio data.

In the case of reproducing an audio title, there is a demand that theimage data be used as supplemental data to the audio data as, forexample, a so-called jacket picture such as lyrics and figure of theplayer. In order to realize this, recording and reproduction apparatuseshaving more flexible and a wider variety of functions are required. Thefunctions include reproduction of video data synchronously with highquality audio data, reproduction of video data asynchronously from audiodata, manipulation of video data by key operation, and special effectsat the time of video data switching.

There is another demand that data be reproduced as the title creatorintended. For example, the initial operation when the disk is insertedshould not be determined by the system used, and direct selection of theaudio data should be permitted or prohibited in accordance with theintention of the title creator regardless of the type of the player.

Conventional optical disks, and recording and reproduction apparatusesgenerally have the above-described structure and thus have a problem inthat it is difficult to record and reproduce high quality digital audiodata along with video data. When the transfer speed of the high qualityaudio data is approximately equal to the reading speed of the opticaldisk, the video data cannot be reproduced along with the audio data bythe method of multiplexing the audio data and the video data used inconventional apparatuses. The reason for this is that when the audiodata and the video data are multiplexed, the transfer speed of theresultant data exceeds the reading speed of the optical disk and thusthe continuous reproduction of such data cannot be guaranteed. Themethod, often used in computer applications, of appropriately bufferingaudio data and video data so as to simultaneously reproduce the audiodata and the video data which are recorded on different areas of theoptical disk cannot be used. The reason for this is that the sum of thetransfer speeds of the audio data and the video data needs to be equalto or lower than the reproduction speed of the optical disk in order tocontinuously reproduce the data recorded on disks such as CDs for anhour or more.

A Browsable reproduction method of switching the video data based on aninstruction by the user while continuously reproducing the audio data,or a SlideShow reproduction method of automatically switching the videodata in synchronization with a specified position in the audio data arenot usable.

SUMMARY OF THE INVENTION

According to one aspect of the invention, a data storage medium havingstored thereon includes an audio sequence including at least one audiostream; at least one video stream; and reproduction control informationfor controlling reproduction of the at least one audio stream and the atleast one video stream. The reproduction control information includesreproduction order information defining the order of at least one videostream, among the at least one video stream stored on the data storagemedium, which is to be reproduced in synchronization with the audiosequence.

In one embodiment of the invention, the reproduction control informationfurther includes video reproduction mode information indicating whetherit is possible or not to change the order of the at least one videostream to be reproduced in synchronization with the audio sequence basedon interaction from a user.

In one embodiment of the invention, the reproduction control informationfurther includes video reproduction mode information indicating whetherreproduction timing of the at least one video stream to be reproduced insynchronization with the audio sequence is defined or a reproductiontime period thereof is defined.

In one embodiment of the invention, the reproduction control informationfurther includes reproduction order mode information defining whetherthe at least one video stream, the order of which is defined by thereproduction order information, is reproduced randomly or sequentially.

In one embodiment of the invention, the reproduction order modeinformation indicates whether the at least one video stream isreproduced randomly while permitting overlap or randomly whileprohibiting overlap.

In one embodiment of the invention, the audio sequence corresponds to atleast one program, and the at least one video stream stored on the datastorage medium is grouped on a program-by-program basis.

According to another aspect of the invention, an apparatus forreproducing information from a data storage medium having stored thereonan audio sequence including at least one audio stream; at least onevideo stream; and reproduction control information for controllingreproduction of the at least one audio stream and the at least one videostream, wherein the reproduction control information includesreproduction order information defining the order of at least one videostream, among the at least one video stream stored on the data storagemedium, which is to be reproduced in synchronization with the audiosequence, the apparatus includes a reading section for reading the audiosequence and the at least one video stream stored on the data storagemedium; and a reproduction section for reproducing the at least onevideo stream in synchronization with the audio sequence in the orderdefined by reproduction order information.

In one embodiment of the invention, the reproduction control informationfurther includes video reproduction mode information indicating whetherit is possible or not to change the order of the at least one videostream to be reproduced in synchronization with the audio sequence basedon interaction from a user.

In one embodiment of the invention, the reproduction control informationfurther includes video reproduction mode information indicating whetherreproduction timing of the at least one video stream to be reproduced insynchronization with the audio sequence is defined or a reproductiontime period thereof is defined.

In one embodiment of the invention, the reproduction control informationfurther includes reproduction order mode information defining whetherthe at least one video stream, the order of which is defined by thereproduction order information, is reproduced randomly or sequentially.

In one embodiment of the invention, the reproduction order modeinformation indicates whether the at least one video stream isreproduced randomly while permitting overlap or randomly whileprohibiting overlap.

In one embodiment of the invention, the at least one video stream to bereproduced in synchronization with the audio sequence is buffered into abuffer located in the reproduction apparatus before reproduction of theaudio sequence.

According to still another aspect of the invention, a method forreproducing information from a data storage medium having stored thereonan audio sequence including at least one audio stream; at least onevideo stream; and reproduction control information for controllingreproduction of the at least one audio stream and the at least one videostream, wherein the reproduction control information includesreproduction order information defining the order of at least one videostream, among the at least one video stream stored on the data storagemedium, which is to be reproduced in synchronization with the audiosequence, the method includes the steps of reading the audio sequenceand the at least one video stream stored on the data storage medium; andreproducing the at least one video stream in synchronization with theaudio sequence in the order defined by reproduction order information.

In one embodiment of the invention, the reproduction control informationfurther includes video reproduction mode information indicating whetherit is possible or not to change the order of the at least one videostream to be reproduced in synchronization with the audio sequence basedon interaction from a user.

In one embodiment of the invention, the reproduction control informationfurther includes video reproduction mode information indicating whetherreproduction timing of the at least one video stream to be reproduced insynchronization with the audio sequence is defined or a reproductiontime period thereof is defined.

In one embodiment of the invention, In one embodiment of the invention,the reproduction control information further includes reproduction ordermode information defining whether the at least one video stream, theorder of which is defined by the reproduction order information, isreproduced randomly or sequentially.

In one embodiment of the invention, the reproduction order modeinformation indicates whether the at least one video stream isreproduced randomly while permitting overlap or randomly whileprohibiting overlap.

In one embodiment of the invention, the at least one video stream to bereproduced in synchronization with the audio sequence is buffered into abuffer located in the reproduction apparatus before reproduction of theaudio sequence.

According to still another aspect of the invention, in a data storagemedium stored with a first system stream and a second system stream tobe reproduced in synchronization with each other, the first systemstream includes reproduction control information indicating timing atwhich the first system stream is reproduced, and the second systemstream is reproduced at timing determined by information other thaninformation included in the second system stream.

According to still another aspect of the invention, an apparatus forreproducing a data storage medium stored with a first system stream anda second system stream to be reproduced in synchronization with eachother, the first system stream includes reproduction control informationindicating timing at which the first system stream is reproducedincludes a reading section for reading the first system stream and thesecond system stream stored on the data storage medium; and a decodersection for decoding the first system stream in accordance with thereproduction control information. The second system stream is decoded inaccordance with a control signal supplied from outside of the decodersection.

According to still another aspect of the invention, a method forreproducing a data storage medium stored with a first system stream anda second system stream to be reproduced in synchronization with eachother, wherein the first system stream includes reproduction controlinformation indicating timing at which the first system stream isreproduced includes the steps of reading the first system stream and thesecond system stream stored on the data storage medium; and controllingthe timing at which the first system stream is reproduced in accordancewith the reproduction control information; controlling the timing atwhich the second system stream is reproduced in accordance withinformation other than information included in the second system stream.

Thus, the invention described herein makes possible the advantages ofproviding (1) an optical disk for realizing reproduction of high qualitydigital audio data along with video data in a restricted range of bitrates; (2) an optical disk, and an apparatus and method for reproducingdata from such an optical disk for realizing switching between a mode inwhich high quality digital audio data and video data are reproducedsynchronously with each other and a mode in which high quality digitalaudio data and video data are reproduced asynchronously from each otherand the video data is switched based on time or by an instruction fromthe user; and (3) a reproduction apparatus for allowing a decoder usedfor a general MPEG2 stream to be used for reproducing audio data andvideo data as independent streams and thus for realizing reproduction ofhigh quality digital audio data along with video data in a restrictedrange of bit rates at a relatively low cost.

These and other advantages of the present invention will become apparentto those skilled in the art upon reading and understanding the followingdetailed description with reference to the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is an external view of an optical disk in a first exampleaccording to the present invention;

FIG. 1B is a cross-sectional view of the optical disk shown in FIG. 1A;

FIG. 1C is an enlarged cross-sectional view of the optical disk shown inFIG. 1A;

FIG. 1D shows pits formed in the optical disk in the first exampleaccording to the present invention;

FIG. 2A shows a track structure of the optical disk shown in FIG. 1A;

FIG. 2B shows a sector structure of the optical disk shown in FIG. 1A;

FIG. 3 shows a logical structure of the optical disk shown in FIG. 1A;

FIG.,4 shows a data structure of an audio manager;

FIG. 5 shows a data structure of an audio title set,

FIG. 6 shows an exemplary structure of an audio object (AOB);

FIG. 7 shows a data structure of PGC information and cell information;

FIG. 8 is a block diagram showing an internal structure of a DVD player,which is a reproduction apparatus;

FIG. 9 shows an example of PGC forming a title;

FIG. 10 shows an example of program information;

FIG. 11 shows an example of cell information;

FIG. 12A shows a process for reproducing audio data without displaying astill picture;

FIG. 12B shows a process for reproducing audio data without displaying astill picture;

FIG. 13A shows a process for reproducing audio data while displaying astill picture;

FIG. 13B shows a process for reproducing audio data while displaying astill picture;

FIG. 14 shows a conventional process for reproducing audio data;

FIG. 15 shows a schematic flow for reproducing a program;

FIG. 16 shows a schematic flow for reproducing a leading audio cell;

FIG. 17 shows a flow for reproducing a silent cell;

FIG. 18 shows a flow for reproducing a continuously reproduced cell;

FIG. 19 is a DVD player and peripheral devices connected thereto;

FIG. 20 shows a remote controller used for operating the DVD player;

FIG. 21 shows a logical structure of a DVD as a multimedia optical diskin a second example according to the present invention;

FIG. 22 shows a structure of an audio manager;

FIG. 23 shows a data structure of an AOB of the DVD in the secondexample;

FIG. 24 shows an exemplary structure of the AOB;

FIG. 25 shows a data structure of PGC information of the DVD in thesecond example;

FIG. 26 is a block diagram showing an internal structure of a DVD playerin the second example;

FIG. 27 is a block diagram showing an internal structure of a DVD playerincluding a system decoder for AOB and P_VOB;

FIG. 28 is a block diagram showing an internal structure of a DVD playerincluding a P_VOB buffer immediately before an AV decoder section;

FIG. 29 shows the relationship among PGC, audio program, cell, pictureprogram, picture cell, AOB and P_VOB;

FIG. 30 shows an example of program information forming a title;

FIG. 31 shows a P_VOB of the DVD in the second example;

FIG. 32 shows an exemplary audio program;

FIG. 33 shows another exemplary audio program;

FIG. 34 shows the number of silent cell packs and audio cell packs ofaudio data of 48 kHz, 16-bit sampling and 2 channels:

FIG. 35 shows picture cell information when the number of still picturepacks is 50;

FIGS. 36A and 36B show methods for reproducing a silent cell and anaudio cell;

FIG. 37 is a flowchart illustrating a method for producing one ofprograms;

FIG. 38 is a flowchart illustrating a method for producing one of theprograms;

FIG. 39 is a flowchart illustrating a method for producing one of theprograms;

FIG. 40 shows a video menu for allowing the user to select a title;

FIG. 41 shows a structure of P_PCI;

FIG. 42 shows a structure of P_DSI;

FIG. 43 shows a logical structure of an optical disk in a third exampleaccording to the present invention;

FIG. 44 shows a data structure of an audio manager (AMG);

FIG. 45 shows a data structure of an audio still video set (ASVS);

FIG. 46 shows a data structure of P_VOB:

FIG. 47 shows a data structure of highlight information;

FIG. 48 shows a data structure of an audio title set (ATS);

FIG. 49 shows a data structure of PGC information (ATS_PGCI);

FIG. 50 illustrates an audio still video display mode;

FIG. 51 shows a data structure of an MPEG system stream;

FIG. 52 shows the relationship among P_VOB, ASVU, ATS_PGCI and AOB;

FIG. 53 shows an example of PGC information;

FIG. 54 shows an example of audio program information (ATS_PGI);

FIG. 55 shows an example of ATS audio still video reproductioninformation (ATS_ASV_PBI);

FIG. 56 shows an example of cell information;

FIG. 57 shows an example of ASV search pointer;

FIG. 58 shows an example of ASVU general information;

FIG. 59A shows the relationship between the audio reproduction timingand the still picture display timing in the “SlideShow” mode;

FIG. 59B shows the relationship between the audio reproduction timingand the still picture display timing in the “Browsable” mode;

FIG. 60 illustrates an audio still video display mode:

FIG. 61 is a block diagram illustrating an internal structure of a DVDplayer as a reproduction apparatus;

FIG. 62 is a flowchart illustrating a method for reproducing PGCinformation;

FIG. 63 is a flowchart illustrating a method for reproducing audioprogram;

FIG. 64 is a flowchart illustrating a method for determining keyoperation;

FIG. 65 is a flowchart illustrating a method for reproducing audio data;

FIG. 66 is a flowchart illustrating a method for reproducing a stillpicture;

FIG. 67 is a block diagram illustrating an internal structure of anotherDVD player as a reproduction apparatus;

FIG. 68 is a block diagram illustrating an internal structure of stillanother DVD player as a reproduction apparatus; and

FIG. 69 illustrates the relationship between DLIST and P_VOB.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, the present invention will be described by way ofillustrative examples with reference to the accompanying drawings.

Example 1

An optical disk in a first example according to the present inventionwill be described.

(1) Physical Structure of the Optical Disk

FIG. 1A shows an external appearance of a DVD 107, which is a multimediaoptical disk. FIG. 1B shows a cross-section of the DVD 107 taken alongline A-A′ in FIG. 1A. FIG. 1C is an enlarged cross-sectional view ofportion B shown in FIG. 1B.

As shown in FIG. 1B, the DVD 107 is formed by sequentially laminating afirst transparent substrate 108, an information layer 109, an adhesivelayer 110, a second transparent substrate 111, and a print layer 112 onwhich a label is to be printed in this order.

The first transparent substrate 108 and the second transparent substrate111 are reinforcement substrates formed of the same material. In theexample shown in FIG. 1B, these substrates each have a thickness ofabout 0.6 mm. These substrates can each have a thickness in the rangebetween about 0.5 mm and about 0.7 mm.

The adhesive layer 110 is provided between the information layer 109 andthe second transparent substrate 111 in order to adhere the informationlayer 109 to the second transparent substrate 111.

On the face of the information layer 109 in contact with the firsttransparent substrate 108 is formed a reflective film (not shown) formedof a thin metal film or the like. By using a molding technique, a highdensity of convex and concave pits are formed in the reflective film.

FIG. 1D shows the shapes of pits formed in the reflective film. In theexample shown in FIG. 1D, each pit has a length of 0.4 μm to 2.13 μm. Aspiral track is formed in the DVD 107. The pits are formed alongside thespiral track so as to be at a distance of 0.74 μm from the spiral trackin a radial direction of the DVD 107. Thus, an array of pits are formedalong the spiral track.

When a light beam 113 is directed toward the DVD 107, a light spot 114is formed on the information layer 109 as shown in FIG. 1C. Theinformation stored on the DVD 107 is detected as a variation in thereflectance of the portion of the information layer 119 which isirradiated by the light spot 114.

The diameter of the light spot 114 of the DVD 107 is about 1/1.6 timesthe diameter of a light spot on a CD because the numerical aperture (NA)of an object lens for DVDs is larger than the numerical aperture of anobject lens for CDs and because the wavelength λ of a light beam forDVDs is shorter than the wavelength λ of a light beam for CDs.

A DVD having the above-described physical structure can store about 4.7Gbytes of information on one side. A storage capacity of about 4.7Gbytes is nearly 8 times the storage capacity of a conventional CD. Sucha large storing capacity of DVDs can greatly improve the quality ofmoving pictures and also greatly extend the reproducible time period ofmoving pictures. Whereas the reproducible time period of a conventionalvideo CD is 74 minutes, a DVD boasts a reproducible time period of 2hours or more.

The fundamental technology which realizes such a large storing capacitylies in reduction of the spot diameter d of a light beam. The spotdiameter d is calculated from the formula: spot diameter d=laserwavelength λ/numerical aperture NA of the object lens. Accordingly, thespot diameter d can be minimized by decreasing the laser wavelength λand increasing the numerical aperture NA of the object lens. It shouldbe noted, however, that increasing the numerical aperture NA of theobject lens can result in coma aberration due to the relative slant ofthe optical axis of the light beam with respect to the face of the disk(i.e., “tilt”). In the case of DVDs, the coma aberration is minimized byreducing the thickness of a transparent substrate. However, reducing thethickness of a transparent substrate can result in another problem oflower mechanical strength of the disk. In the case of DVDs, the strengthof the transparent substrate is reinforced by attaching anothersubstrate to the transparent substrate, thereby overcoming the problemsassociated with the mechanical strength of the disk.

A red semiconductor laser having a short wavelength of 650 nm and anobject lens having a large numerical aperture (NA) of about 0.6 mm areused to read the information stored on a DVD. By employing a thintransparent substrate having a thickness of about 0.6 mm in addition tothe above-mentioned laser and object lens, it is possible to store about4.7 Gbytes of information on one side of an optical disk having adiameter of 120 mm.

FIG. 2A schematically illustrates a spiral track 20 formed from theinner periphery toward the outer periphery of the information layer 109of the DVD 107 (FIG. 1A). The spiral track 20 is divided into prescribedunits referred to as sectors. In FIG. 2A, the respective sectors aredenoted by S1, S2, . . . , S99, and S100. The information stored on theDVD 107 is read on a sector-by-sector basis.

FIG. 2B shows an internal structure of a sector, where the sectorincludes a sector header region 21, a user data region 22, and an errorcorrection code storage region 23.

The sector header region 21 stores a sector address for identifying thesector and an error detection code therefor. Based on these sectoraddresses, a disk reproduction apparatus determines one of a pluralityof sectors from which information should be read.

The user data region 22 stores a 2 Kbyte long data string.

The error correction code storage region 23 stores error correctioncodes for the sector header region 21 and the user data region 22included in the same sector. A disk reproduction apparatus performserror detection by using the error correction codes when reading datafrom the user data region 22 and performs error correction based on theerror detection results, thereby insuring the reliability of datareading.

(2) Logical Structure of the Optical Disk

FIG. 3 shows a logical structure of the DVD 107 (FIG. 1A). As shown inFIG. 3, the region of the DVD 107 is divided into a lead-in region 31, avolume region 32, and a lead-out region 33. These regions can beidentified by identification information included in sector addresses ofphysical sectors. The physical sectors are arrayed in an ascending orderbased on their sector addresses.

In the lead-in region 31, data for stabilizing the operation of areproduction apparatus at the beginning of read, for example, is stored.

No meaningful data is stored in the lead-out region 33. The lead-outregion 33 is used for informing the disk reproduction apparatus of thetermination of reproduction.

The volume region 32 stores digital data corresponding to anapplication. The physical sectors included in the volume region 32 aremanaged as logical blocks. The logical blocks are identified bysequential numbers (logical block numbers) respectively assigned to thephysical sectors after the first physical sector (designated as the 0thphysical sector) in the volume region 32.

As shown in FIG. 3, the volume region 32 is subdivided into a volumefile management region 32 a and an audio zone region 32 c.

The volume file management region 32 a stores file system managementinformation for managing a plurality of logical blocks as files inaccordance with ISO13346. The file system management information isinformation indicating the correspondence between the name of each of aplurality of files and the addresses of the logical blocks occupied bythat file. A disk reproduction apparatus achieves file-by-file access tothe optical disk based on the file system management information.Specifically, the disk reproduction apparatus refers to the file systemmanagement information to obtain the addresses of the logical blockscorresponding to a given file name, and accesses the logical blocksbased on these addresses. As a result, the digital data contained in adesired file can be read.

An audio zone region 32 c stores an audio manager 900 and one or moreaudio title sets 800.

The audio title set 800 contains a plurality of pieces of audio data andmanagement information for managing the order of reproducing theplurality of pieces of audio data. An audio title set 800 has a datastructure which allows for management of the audio data in units whichare referred to as audio titles. Typically, an audio title correspondsto a music album containing one or more tunes.

(3) Data Structure of the Audio Zone Region 32 c

The audio zone region 32 c stores an audio manager 900 and one or moreaudio title sets 800.

(3.1) Data Structure of the Audio Title Set 800

FIG. 5 shows a data structure of an audio title set 800. The audio titleset 800 includes a plurality of audio objects (hereinafter, referred toas “AOBs”) 802, audio title set management information (ATSI) 801 formanaging the order of reproducing the plurality of AOBs 802, and audiotitle set management information backup (ATSI_BUP) 804 which is backupdata of the audio title set management information 801. In the followingdescription, an “audio title set” will generally be referred to as an“ATS”.

(3.1.1) Data Structure of the AOB 802 The AOB 802 is packetized into 2Kbytes. The AOB 802 stores data in the LPCM format, AC3 format, DTSformat or other compression formats. In the case of the LPCM format, thesample bit is 16, 20, or 24 bits, with a sampling frequency of 48 kHz,96 kHz, 192 kHz, 44.1 kHz, 88.2 kHz, or 176.4 kHz.

(3.1.2) Data Structure of the Audio Title Set Management Information 801

The audio title set management information (ATSI) 801 includesinformation for managing the order of reproducing the AOBs 802. Theorder of reproducing the AOBs 802 is designated by a program chain(PGC), as in the case of video objects (VOBs). Different PGCs can definedifferent orders of reproduction of AOBs 802.

As shown in FIG. 5, the audio title set management information (ATSI)801 includes an ATS management table (ATSI_MAT) 811 and a PGC managementinformation table (ATS_PGCIT) 812.

The ATS management table 811 serves as header information of the audiotitle set management information 801. The ATS management table 811includes a pointer indicating a region in which each AOB 802 is stored,a pointer indicating a region in which the PGC management informationtable 812 is stored, and attribute information on each AOB 802. In thecase where a still picture is stored on the DVD 107 (FIG. 1A), the ATSmanagement table 811 also includes attribute information and the likefor the still picture.

The PGC management information table (ATS_PGCIT) 812 includes ATS PGCmanagement table information (ATS_PGCITI) 831, a plurality of ATS PGCinformation search pointers (ATS PGCI_SRPs) 832, and a plurality of PGCinformation (ATS_PGCI) units 833.

The ATS PGC information search pointers (ATS_PGCI_SRPs) 832 are indicesfor a plurality of PGCs stored in the PGC management information table812 and designate the PGC information to be executed first on atitle-by-title basis.

Each of the PGC information units describes positions on the opticaldisk 107 where one or more audio objects are recorded and the order ofreproduction thereof. Reproduction of the same audio object can bedescribed by different PGC information. Specifically, each PGCinformation unit includes “ATS PGC general information (ATS_PGC_GI)”,“ATS program information table (ATS_PGIT) ”, and “audio cellreproduction information table (ATS_C_PBIT)”.

FIG. 7 shows a data structure of each PGC information unit. As shown inFIG. 7, “ATS PGC general information (ATS_PGC_GI)” includes the numberof programs and the number of cells included in the PGC information, thereproduction time period of the PGC, and information on pointers to “ATSprogram information table (ATS_PGIT)” and to “audio cell reproductioninformation table (ATS_C_PBIT)”.

The “ATS program information table (ATS_PGIT)” includes “programphysical allocation information” indicating whether or not the AOB ofeach program and the AOB of the previous program are recorded atphysically discontinuous positions on the optical disk, “program timeattribute information” indicating whether or not the time information ofthe AOB is continuous with the time information of the previous AOB,“program start cell number” indicating the first cell number forming theprogram, “program still picture flag” indicating whether or not theprogram includes a still picture, “reproduction start audio cell time”indicating the first time information of the first audio cell includedin the program, “program total reproduction time period” indicating thereproduction time period of the program, and “audio pause time period”indicating the silent period until the reproduction of the audio cell ofthe program starts.

The “audio cell reproduction information table (ATS_C_PBIT)” stores cellinformation forming the AOB to be reproduced. Specifically, the “ATScell reproduction information table” includes “cell index number”indicating the order of cells included in the program, “cell type”indicating the attribute of the cell (i.e., whether the cell is a stillpicture cell, a silent cell or an audio cell), “cell start address”indicating the start address of the cell in the form of a relativeaddress with respect to the first pack of the AOB of the ATS includingthe cell, and “cell termination address” indicating the final address ofthe cell in the same manner.

FIG. 6 shows an exemplary structure of the AOB. The AOB is part of anMPEG2 stream and includes a still picture cell including a still picturepack, a silent cell including an audio pack including substantiallysilent audio data, and an audio cell including an audio pack of audiodata forming a tune. The AOB includes one or more audio cells and maynot include a still picture cell or a silent cell. Still picture cellsare never continuous with each other and silent cells are nevercontinuous with each other. A still picture cell is always followed by asilent cell or an audio cell. A silent cell is always followed by anaudio cell. In the example shown in FIG. 6, audio cells and silent cellsexist and are physically continuous. Time information is alsocontinuous; i.e., the “program physical allocation information ” has avalue representing “continue”, and the “program time attributeinformation” also has a value representing “continue”.

In FIG. 6, the line passing through points B, C, E, F and G represents achange in the value of the time information (i.e., PTS) of the AOB.Point A represents a value of the PTS of the still picture cell. Point Brepresents a value of the first PTS of a silent cell. Point C representsa value of the first PTS of an audio cell. Thus, the PTS of a silentcell is continuous to the PTS of an audio cell, and there is no dataunderflow gap, as referred to with respect to the MPEG2 stream, betweenthe silent cell and the audio cell. Point B, at which the value of thePTS of the silent cell is larger than the value of the PTS of the stillpicture cell, represents that a still picture in the still picture cellis displayed before the reproduction of the silent cell starts. The PTSof the next still picture cell is represented by point D, and the PTS ofthe next silent cell is represented by point E. In the case where thePTS of the still picture cell and the PTS of the silent cell have anequal value, the reproduction of the silent cell starts simultaneouslywhen the still picture is displayed. The difference between the firstPTS of the next audio cell at point F and the final PTS of the audiocell at point D is “audio pause time period”. Since the gap between thePTS's needs to be 0.7 seconds or less as specified by MPEG2, thedifference at point B between the first PTS of the silent cell and thePTS of the still picture cell, and the difference at point D between thefirst PTS of the still picture cell and the final PTS of the audio cellneed to fulfill such a condition.

FIG. 9 shows an exemplary PGC forming a title. The example shown in FIG.9 includes five programs. Programs #1 and #2 correspond to AOB #1, andprograms #3, #4 and #5 correspond to AOB #2. On the information storingmedium, AOB #1 is recorded after AOB #2. Programs #1 and #2 both includea still picture cell and a silent cell, and program #2 includes twoaudio cells. Programs #3 and #4 includes only a silent cell, and program#5 includes only an audio cell.

In the case where all the audio cells each have a reproduction timeperiod of 60 seconds (5,400,000 in PTS), all the silent cells each havea reproduction time period of 1 second (90,000 in PTS), and the PTS ofthe still picture cell has the same value as that of the first PTS ofthe silent cell, program information can be described as shown in FIG.10. Under the conditions that the size of the still picture data isabout 1.88 Mbits and the audio data is 48 kHz, 16 bit sampling with 2channels, the number of the still picture packs is 112, the number ofthe silent cell packs is 96, and the number of the audio cell packs is5760 as shown in FIG. 11.

The audio title set has been described. Next, with reference to FIG. 4,the audio manager will be described.

(3.2) Data Structure of the Audio Manager 900

The audio manager 900 is information for controlling the reproductionwhich is to be first referred to for performing audio-orientedreproduction of the information on the optical disk by a reproductionapparatus.

FIG. 4 shows a data structure of the audio manager 900.

The audio manager 900 includes “audio manager information (AMGI)”, “VOBfor audio manager menu (AMGM_VOBS)”, and “audio manager informationbackup (AMGI_BUP)”.

The “audio manager information (AMGI)” includes “audio managerinformation management table (AMGI_MAT)” including attribute informationand pointer information, “audio title management information” indicatingthe number of audio titles and the like, “audio title search pointer(ATT_SRP)” indicating search information on the audio titles, and “audiomanager menu PGC management information table (AMGM_PGCI_UT)” indicatingPGC information for audio manager menu.

Each “audio title search pointer (ATT_SRP)” includes “audio title type”indicating the type of each title, “number of programs in the titles”indicating the number of programs included in the titles, “titlereproduction time period” indicating the reproduction time period of thetitles, “ATS number” indicating the set number of the ATS to which eachtitle belongs, “ATS title number” indicating the title number of eachtitle in the ATS, and “ATS address” indicating the address of the ATS towhich each title belongs.

The audio zone region and the DVD as a multimedia optical disk have beendescribed. Next, a reproduction apparatus according to the presentinvention will be described.

First, an external appearance of a DVD player, which is a reproductionapparatus for multimedia optical disks will be described. FIG. 19 showsexternal appearances of a DVD player 1, a TV monitor 2 and a remotecontroller 91.

The DVD player 1 has an opening in a front face of a chassis thereof,and includes a driving mechanism for loading an optical disk in thedepth direction of the opening.

Provided on the front face of the DVD player 1 is a remote controlreceiving section 92 having a light receiving element for receivinginfrared rays emitted by the remote controller 91. When an operator usesa remote controller held in his/her hand, the remote control receivingsection 92 sends an interrupt signal indicating that a key signal hasbeen received.

Provided on a rear face of the DVD player 1 are video and audio outputterminals. A video signal reproduced from the DVD can be output to thelarge TV monitor 2 for home use by connecting an AV cord to the videoand audio output terminals. Thus, the operator can enjoy the videoreproduced from the DVD on a large TV of, for example, 33 inches or 35inches. As can be appreciated from the above description, the DVD player1 in this example is not used in the state of being connected to apersonal computer but is used with the TV monitor 2 as an electronicappliance for home use.

The remote controller 91 includes a spring-loaded keypad on a surface ofa casing thereof, and outputs a code corresponding to a pressed key byinfrared rays. FIG. 20 shows an operation panel of the remote controller91. The “POWER” key on the operation panel is for turning the DVD player1 ON or OFF. The “MENU” key is used for retrieving the volume menu ofthe optical disk during reproduction of the program chain. Ten keys areused for, for example, chapter-jumping the movie or selecting musictunes. Upward, downward, leftward and rightward cursor keys are used forselecting items. The “ENTER” key is used for confirming an item selectedby the cursor. When the cursor is moved on items by the upward,downward, leftward and rightward cursor keys, the item on which thecursor is positioned is displayed with a select color of item colorinformation of the management information pack. When the item isconfirmed by the “ENTER” key, the item is displayed with a confirmationcolor. In addition, there are keys which are common with other AVapparatuses such as, f or example, “PLAY”, “STOP”, “PAUSE”, “FORWARD”and “REWIND” keys.

Next, the structure of the DVD player, which is a reproduction apparatusfor multimedia optical disks will be described.

FIG. 8 is a block diagram of an internal structure of a DVD player 70.The DVD player 70 includes a driving mechanism 81, an optical pickup 82,a mechanism control section 83, a signal processing section 84, an AVdecoder section 85, a remote control receiving section 92 and a systemcontrol section 93.

The driving mechanism 81 includes a table on which an optical disk isset and a spindle motor for clamping and rotating the optical disk whichis set on the table. The table is structured to be moved in and out ofthe chassis by an eject mechanism not shown. When the table is out ofthe chassis, the operator sets an optical disk onto the table. When theoptical disk is set on the table and the table is moved back into thechassis, the optical disk is loaded on the DVD player 70.

The mechanism control section 83 controls a mechanical system includingthe motor for driving the disk and the optical pickup 82 for reading asignal recorded on the disk. Specifically, the mechanism control section83 adjusts the motor speed in accordance with the position of the trackindicated by the system control section 93. The mechanism controlsection 83 also controls an actuator of the optical pickup 82 to movethe optical pickup 82. When an accurate track is detected by servocontrol, the mechanism control section 83 instructs the optical disk towait until a desired physical sector on the rotating optical diskreaches the position of the optical pickup 82. Then, signals arecontinuously read from the desired position.

The signal processing section 84 processes the signal read from theoptical pickup 82 with, for example, amplification, waveform shaping,binarization, demodulation, and error correction to convert the signalinto a digital data stream, and then stores the resultant data stream ina buffer memory in the system control section 93 (described below) on alogical block-by-logical block basis.

The AV decoder section 85 processes the digital data, which is an inputVOB, in a prescribed manner to convert the data into a video signal oran audio signal. Specifically, the AV decoder section 85 includes asystem decoder 86, a video decoder 87 and an audio decoder 88.

The system decoder 86 receives the digital data stream transferred fromthe buffer memory on a logical block-by-logical block basis (i.e., on apacket-by-packet basis) and distinguishes a stream ID and a sub streamID in the header of each packet, thereby classifying the data into amoving picture data pack, an audio data pack and a managementinformation pack. At this point, the moving picture data pack is outputto the video decoder 87. Regarding the audio data pack, only an audiodata pack having a designated stream number is output to the audiodecoder 88 in accordance with a decode stream instruction command sentfrom the system control section 93. The management information pack isoutput to the system control section 93. The moving picture data packinput to the video decoder 87 is extended by the prescribed formatdefined by the MPEG2 format and output as digital video data. Then, thedigital video data is converted into a video signal of the NTSC formatand externally output. The audio data input to the audio decoder 88 isdecoded in the LPCM or AC3 format in accordance with the data type, D/Aconverted, and then externally output as an audio signal.

The audio decoder 88 processes the digital data, which is an input AOB,in a prescribed manner in accordance with the data type, converts thedata into an audio signal, and externally outputs the data.

The system control section 93 includes a working memory and a CPUintegrated together and performs the overall control of the DVD player70.

The reproduction apparatus according to the present invention operatesin, for example, the following manner.

When a DVD is loaded in the DVD player 70, the system control section 93detects that a DVD is loaded from the optical sensor or the like. Then,the system control section 93 controls the mechanism control section 83and the signal processing section 84, thereby controlling rotation ofthe DVD so as to cause the optical pickup 82 to seek to the lead-inregion. Thus, the DVD player 70 is initialized and reproduction starts.

For starting the reproduction, the system control section 93 determineswhether or not the DVD player 70 is in a video-oriented reproductionmode, by a reproduction mode determination section. When it isdetermined that the DVD player 70 is in the video-oriented reproductionmode, the system control section 93 reads the video manager based on theinformation which is read from the volume file management region. Thesystem control section 93 refers to the PGC management information tablefor the video manager menu to calculate the recording address of the PGCfor the volume menu. The resultant PGC is reproduced and retainedinside. When the PGC for the volume menu is retained inside, the systemcontrol section 93 refers to the retained PGC information to calculatethe video object (VOB) to be reproduced and the recording address of theVOB on the optical disk. When the VOB to be reproduced is determined,the system control section 93 outputs a control signal to the mechanismcontrol section 83 and the signal processing section 84 so as toretrieve the determined VOB from the DVD for reproduction. Thus, thevideo menu from which the user can select the title to be reproduced isdisplayed.

The user sees the menu and selects and confirms the title that he/she isinterested in by designating the item number in the menu using theremote controller. Then, the system control section 93 receives thedesignation of the item number in the menu from the remote controllerand refers to the management information pack included in the VOB of thevideo menu which is being reproduced, the VOB being input from the AVdecoder section 85, to execute a control command corresponding to thedesignated number. The control command is PlayTitle #n or the like, andthe title number to be reproduced is designated by “n”. As an executionoperation by the PlayTitle command, the system control section 93 refersto the title search pointer table, which is a part of the audio manager,to determine the audio title set (ATS) to which the designated titlebelongs to and the title number in the ATS. When the ATS is confirmed,the system control section 93 outputs a control signal to the mechanismcontrol section 83 and the signal processing section 84 so as toreproduce the ATS management information of the confirmed title set andretrieves the title search pointer table of the ATS, which is a part ofthe ATS management information, to the system control section 93. Whenthe title search pointer table is retrieved, the system control section93 refers to the table to determine the PGC information for starting thereproduction of the title to be reproduced. When the PGC information isdetermined, the system control section 93 outputs a control signal tothe mechanism control section 83 and the signal processing section 84 soas to reproduce the determined PGC information and retain theinformation in the inside buffer memory for the PGC information. Whenthe PGC information is retained, the system control section 93 refers tothe retained PGC information to determine the audio object (AOB) to bereproduced and the recording address thereof. Then, the AOB isreproduced by a control signal output to the mechanism control section83 and the signal processing section 84 from the system control section93.

The system control section 93 sequentially determines the AOBs to bereproduced and controls the reproduction thereof in accordance with theretained PGC information. When the reproduction of the final AOBindicated by the PGC information is completed, the system controlsection 93 searches for the PGC information of the next title andreproduces the AOBs described in the PGC information in the same manner.Thus, all the titles are reproduced and the operation is stopped. Inaccordance with specific setting of the DVD player or the DVD, only onetitle can be reproduced before the operation is stopped, or a menu canbe displayed after reproduction of one or more titles is completed.

Next, a method for reproducing a still picture cell, a silent cell andan audio cell will be described in detail.

FIG. 14 shows a conventional method for reproducing the audio cell.Conventionally, for reproducing an MPEG2 stream, the leading end of theaudio cell pack is first sought and data reading starts. However, audiooutput does not immediately start but starts after an idle time period,which is predetermined in each reproduction apparatus. The idle timeperiod includes a time period required for determining the PTS of theaudio data, a time period required for determining that data is correct,and a time period required for the muting circuit in an analog outputsection to be transitioned from a mute state to a non-mute state. Thus,the idle time period varies in accordance with the type of reproductionapparatus. Especially when the reproduction section and the decoder areaccommodated in separate chassis, the idle time period tends to beextended because determination on the PTS and the determination on thecorrectness of the audio data are separately performed.

FIGS. 12A and 12B show methods for reproducing only audio data withoutdisplaying a still picture even though the still picture is included.FIG. 12A shows the method in the case where the reproduction isperformed from the leading end of the data, and FIG. 12B shows themethod in the case where the reproduction is performed in continuationfrom the previous cell.

In the case where reproduction is performed from the leading end of thedata by selecting a title or program from the menu or the like throughjumping, the leading pack of the silent cell is jumped to with referenceto the start address of the cell information. At this point, the STC,which is the reference time of the decoder is set with the SCR of theleading pack of the silent cell. Next, skipping and jumping of datacorresponding to a prescribed idle time period are performed withreference to the PTS of the silent cell, and the silent cell for theidle time period is reproduced. Audio output is prepared for during thisperiod. At this point, the next title number is not displayed on thedisplay device of the reproduction apparatus, and the passage ofreproduction time period is not updated. In the case where the audiooutput is started and display of the title number and the updating ofthe passage of the reproduction time period are performed simultaneouslywhen the first PTS of the leading cell is detected, the reproductionapparatus behaves as if the audio data is output simultaneously with thecompletion of the jump such as menu selection. In the case where thereproduction is performed in continuation from the previous cell, astill picture pack is jumped over and a silent cell is jumped over orskipped except for the idle time period. At this point, by continuouslycounting the STC, which is reference for the system time, the intervalbetween the completion of the audio output by the previous cell and thestart of the audio output by the next cell equals the audio pause timeperiod. The counting of the STC is continued when the physicalallocation information and the time attribute information both have avalue indicating “continue”. When either one of them indicates“no-continue”, the same processing as in the jump from the menu isperformed, and thus the STC is reset at the leading end of the silentcell pack. Even in the case where there is no still picture cell, themethod is substantially the same as described above. In the case wherethere is no silent cell and the reproduction starts from the leading endof the data, the operation is similar to the conventional operationshown in FIG. 14. In the case where the reproduction is performed incontinuation from the previous cell, the operation is as follows. Whenthe time attribute information indicates “continue”, the audio cell isdecoded continuously from the previous cell and audio data is output.When the time attribute information indicates “no-continue”, theoperation is the same as the conventional operation shown in FIG. 14 asin the case where the reproduction is performed from the leading end ofthe data.

FIGS. 13A and 13B show methods for reproducing the audio data whiledisplaying a still picture. FIG. 13A shows the method in the case wherethe reproduction is performed from the leading end of the data, and FIG.13B shows the method in the case where the reproduction is performed incontinuation from the previous cell.

In the case where the reproduction is performed from the leading end ofthe data or by selecting a title or program from the menu or the likethrough jumping, the pack of the still picture cell is sought from thecell information. Thus, the still picture cell is read and decoded. Atthis point, the STC, which is the reference time of the decoder, is setwith the SCR of the leading pack of the still picture cell. Next, theleading pack of the silent cell is read. When an STC reaches an STC ofthe still picture cell, the still picture is displayed. The rest of theoperation is the same as the operation when there is no still picture.The display of the still picture can be during the processing of thesilent cell, simultaneously with the start of output of the audio cell,or after the start of output of the audio cell in the range permitted bythe MPEG2 format. In the case where the reproduction is performed incontinuation from the previous cell, the still picture cell is read anddecoded when a still picture pack is detected. Next, the silent cell isprocessed. Whether or not the STC is set depends on the time attributeinformation as in the case where there is no still picture cell. Therest of the operation is the same as the operation when no still pictureis displayed, except that the still picture is displayed when the STCbecomes a PTS of the still picture cell and that the STC is set with theSCR of the leading pack of the still picture cell.

FIGS. 15 through 18 are flowcharts each illustrating a program. In thecase where the physical allocation information of the programinformation shows “continue” and the program previously reproduced has aprogram number which is smaller by one than the program number of theprogram to be reproduced now, seek to the reading head for the DVD isnot specifically necessary. When the time attribute informationindicates “continue” and the reproduction is performed in continuationfrom the previous program, the STC, which is the reference time for thedecoder, does not need to be reset.

The determination of whether or not the cell is a still picture cell canbe performed using the cell type in the cell information or using astill picture flag of the program information. The determination ofwhether or not the cell is a silent cell is performed by the cell typein the cell information. The determination that the cell is the finalcell is performed by comparing the termination address of the cellinformation and the address read from the data in the DVD. Thecompletion of the reproduction of the program can be determined by thecell index of the cell information returning to zero, the cell typeindicating a still picture cell or a silent cell, or the start cellnumber of the next program in the program information.

The skipping of the silent cell is performed while detecting the PTSwhen the silent cell is decoded or by obtaining the number of packs tobe skipped based on the data rate.

As described above, in the first example according to the presentinvention, program reproduction information including the start time andreproduction time period of each of audio data based on the reproductionstart time of the leading audio data in an MPEG2 stream is recorded inthe management region as a part of the reproduction control information.Accordingly, a multimedia information storing medium which realizesreproduction of high quality digital audio data and video data addedthereto under a restricted bit rate can be provided. The intervalbetween the reproduced audio data can be uniform even in low-costreproduction apparatuses or reproduction apparatuses having noreproduction function for video data. Thus, title creators can preparedata easily.

Example 2

An optical disk, and an apparatus and method for reproducing informationfrom the optical disk in a second example according to the presentinvention will be described. Identical elements previously discussed inthe first example bear identical reference numerals and the descriptionsthereof will be omitted.

(1) Physical Structure of the Optical Disk

The physical structure of the optical disk is identical with thatdescribed in the first example and thus the description thereof will beomitted.

(2) Logical Structure of the Optical Disk

The logical structure of the optical disk is identical with thatdescribed in the first example and thus the description thereof will beomitted.

(3) Data Structure of the Audio Zone Region 32 c

The audio zone region 32 c stores an audio manager 900 and one or moreaudio title sets 800 as in the first example. The data structure of theaudio manager 900 and the data structure of the audio title sets 800 aredifferent from those in the first example.

(3.1) Data Structure of the Audio Title Set 800

FIG. 23 shows a data structure of the audio title set 800 in the secondexample. The audio title set 800 includes a plurality of audio objects(hereinafter, referred to as “AOBs”) 802, a plurality of picture videoobjects (hereinafter, referred to as “P_VOBs” 1002), audio title setmanagement information (ATSI) 801 for managing the order of reproducingthe plurality of AOBs 802 and the plurality of P_VOBs 1002, and audiotitle set management information backup (ATSI_BUP) 804 which is backupdata of the audio title set management information 801. In the followingdescription, an “audio title set” will generally be referred to as an“ATS”.

(3.1.1) Data Structure of the AOB 802

The data structure of the AOB 802 of the optical disk is identical withthat described in the first example and thus the description thereofwill be omitted.

(3.1.2) Data Structure of P_VOB 1002

FIG. 31 shows a data structure of the P_VOB 1002. The P_VOB 1002includes a picture NV pack (P_NV_PCK) 1003, a plurality of video packs(V_PCK) 1004, and a plurality of sub-picture packs (SP_PCK) 1005.

Unlike in the case of DVD-Video, the P_VOB 1002 includes one picturevideo object unit (P_VOBU), and only one picture NV pack (P_NV_PCK) 1003is included.

The sub-picture packs (SP_PCK) 1005 can each have a plurality ofsub-picture streams and has an identification code as in the case ofDVD-Video. The sub-picture packs (SP_PCK) 1005 can be omitted.

The P_VOB 1002 does not include audio data, unlike in the case ofDVD-Video. The picture NV pack (P_NV_PCK) 1003 includes a P_PCI packetand a P_DSI packet in a similar manner as a PCI packet and a P_DSIpacket of DVD-Video.

As shown in FIG. 41, the P_PCI includes P_VOBU to which the P_PCIbelongs to (i.e., attribute information, reproduction time information,highlight information and the like of P_VOB), as in the case ofDVD-Video, but does not include address information.

As shown in FIG. 42, the P_DSI includes an SCR of the NV_PCK to whichthe P_DSI belongs, and a termination address of the P_VOBU, i.e., P_VOBto which the P_DSI belongs, and address information of a pack includingthe final data of the first I picture of the video pack (P_PCK) as inthe case of DVD-Video, but does not include other information.

(3.1.3) Data Structure of the Audio Title Set Management Information 801

The audio title set management information (ATSI) 801 includesinformation for managing the order of reproducing the AOBs 802 and theP_VOB 1002. The order of reproducing the AOBs 802 is designated by aprogram chain (PGC), as in the case of video objects (VOBs).

The data structure of the audio title set management information 801 isidentical with that shown in FIG. 5 except for the data structure of thePGC information 833.

Each of the PGC information units describes positions on the opticaldisk where one or more audio objects are recorded and the order ofreproduction thereof. Reproduction of the same audio object can bedescribed by a different PGC information unit. Specifically, the PGCinformation includes “ATS PGC general information (ATS_PGC_GI)”, “ATSprogram information table (ATS_PGIT)”, “audio cell reproductioninformation table (ATS_C_PBIT)”, “ATS picture program information table(ATS_PPGIT)”, and “ATS picture cell reproduction information table(ATS_PC_PBIT)”.

FIG. 25 shows a data structure of the PGC information. As shown in FIG.25, “ATS PGC general information (ATS_PGC_GI)” includes the number ofpicture programs, the number of audio programs and the number of cellsincluded in the PGC information; the reproduction time period of thePGC; and information on pointers to a picture program reproduction mode,picture program reproduction control, the “ATS program information table(ATS_PGIT)”, “audio cell reproduction information table (ATS_C_PBIT)”,“ATS picture program information table (ATS_PPGIT)”, and “ATS picturecell reproduction information table (ATS_PC_PBIT)”.

The “ATS program information table (ATS_PGIT)” includes a plurality“audio program information (ATS_PGI)” units included in the PGC. Each ofthe plurality of “audio program information (ATS_PGI)” units includes“audio program physical allocation inforamtion” indicating whether ornot the AOB of each program and the AOB of the previous program arerecorded at physically discontinuous positions on the optical disk,“audio program time attribute information” indicating whether or not thetime information of the AOB is continuous with the time information ofthe previous AOB, “audio program start cell number” indicating the firstcell number forming the audio program, “reproduction start audio celltime” indicating the first time information of the first audio cellincluded in the audio program, “audio program total reproduction timeperiod” indicating the reproduction time period of the audio program,and “audio pause time period” indicating the silent period until thereproduction of the audio cell of the audio program starts.

The “audio cell reproduction information table (ATS_C_PBIT)” stores cellinformation forming the AOB to be reproduced as in the first example.

The “ATS picture program information table (ATS_PPGIT)” includes aplurality of “ATS picture program information” units. Each ATS pictureprogram information unit includes a used SP number (PPG_SP_STN)describing a stream number of a sub-picture used in the picture program,an initial button number (PPG_FOSL) indicating the number of a buttonwhich is in the highlight information used in the picture program and isselected in an initial state, a picture transition mode (PPG_T_mode)indicating a transition mode of a still picture in the program, a stillpicture identification code (PPG_ISRC_SPCT) indicating an ISRC code ofthe still picture in the program, a picture cell start PTS (PC_S_PTM)indicating a PTS of a first pack of the picture cell of the program, apicture program reproduction time period (ATS_PPG_PB_TM) which is areproduction time period of the program, a start section transition timeperiod (PPG_TI_TM) indicating the transition time period at the time ofstarting the reproduction of the still picture of the program, and atermination section transition time period indicating the transitiontime period at the time of terminating reproduction of the still pictureof the program.

In this example, as the picture transition modes, “no transition”,“fading from black”, “fading into black”, “cross-fading”, and “wiping inseveral directions” are assumed. Each of the programs includes one cell.Since each cell has an independent P_VOB, the reproduction time periodof the picture program is a 1-frame time period.

The “ATS picture cell reproduction information table (ATS_PC_PBIT)”includes a cell still time period (P_C_Still_Time) indicating acontinuous time period during which the picture cell is displayed, astart address (P_C_FVOBU_SA) of a cell of the picture program, and atermination address (P_C_LVOBU_SA) indicating an address of the finalpacket of the cell.

FIG. 24 shows an exemplary structure of the AOB. The AOB is a part of anMPEG2 stream and includes a silent cell including an audio packincluding substantially silent audio data and an audio cell including anaudio pack of audio data forming a tune. The AOB includes one or moreaudio cells and may not include a silent cell. A silent cell is neverfollowed by another silent cell and is always followed by an audio cell.In the example shown in FIG. 24, audio cells and silent cells exist andare physically continuous. Time information is also continuous: i.e.,the “audio program physical allocation information” has a valuerepresenting “continue”, and the “audio program time attributeinformation” also has a value representing “continue”.

In FIG. 24, the line passing through points B, C, E, F and G representsa change in the value of the time information (i.e., PTS) of the AOB.Point B represents a value of the first PTS of a silent cell. Point Crepresents a value of the first PTS of an audio cell. Thus, the PTS of asilent cell is continuous to the PTS of an audio cell, and there is nodata underflow gap, as referred to with respect to the MPEG2 stream,between the silent cell and the audio cell. In a similar manner, the PTSof the next silent cell is represented by point E. The differencebetween the first PTS of the next audio cell at point F and the finalPTS of the audio cell at point D is an “audio pause time period”. Sincethe PTS's need to be continuous in one stream as specified by MPEG2, thechange in the PTS is linear as shown in FIG. 24.

With reference to FIGS. 31, 41 and 42, the picture video object (P_VOB)will be described in detail. As described above, the leading pack of theP_VOB 1002 is a picture NV pack (P_NV_PCK) 1003 including a P_PCT packetand a P_DSI packet having time information, position information andhighlight information. Only one picture NV pack (P_NV_PCK) 1003 alwaysexists at the leading end thereof. The picture NV pack (P_NV_PCK) 1003is followed by video packs (V_PCK) 1004 which are MPEG2 video packs forstoring video data and sub-picture packs (SP_PCK) 1005 for dividingsub-picture streams which are permitted to be included up to 32 streamsand storing the divided sub-picture streams. In FIG. 31, 2 sub-picturestreams 1005 (SP#1 and SP#2) are included and each sub-picture stream isdivided into 2 packs. In FIG. 31, the video packs (V_PCK) 1004 precedethe sub-picture packs (SP_PCK) 1005, but there is no limitationregarding the order as long as the MPEG2 standards are fulfilled.Although termination codes such as program encodes or the like are notshown in FIG. 31, such termination codes can be included as long as therequirements of MPEG2 streams are fulfilled. Such termination codes neednot be included since the P_VOB 1002 is a part of the MPEG2 programstream.

FIG. 41 shows a structure of the P_PCI information included in the P_PCIpacket. The P_PCI information includes P_PCI general information, P_PCIhighlight information, and P_PCI recording information. The P_PCIgeneral information includes a P_VOBU type (P_VOBU_CAT) describing thetype of the analog copy protection with respect to the P_VOBU videodata, P_VOBU start time (P_VOBU_S_PTM) describing the PTS of the firstvideo to be displayed included in the P_VOBU, P_VOBU termination time(P_VOBU_E_PTM) describing the PTS of the final video to be displayedincluded in the P VOBU, P_VOBU SEQ time (P_VOBU_SEQ_E_PTM) describingthe PTS including the SEQ existing in the P_VOBU, and P_VOBU cellreproduction time (P_VOBU_C_ELTM) indicating relative time in a picturecell of the first video to be displayed of the P_VOBU. The P_VOB isalways an I picture of 1 VOBU, 1 cell and 1 video frame, and alwaysincludes SEQ. Accordingly, the P_VOBU_S_PTM, P_VOBU_E_PTM,P_VOBU_SE_E_PTM have an identical value, and the P_VOBU_E_ELTM indicates0.

The P_PCI highlight information includes P_PCI highlight generalinformation (P_PCI_HL_GI) describing the start time, termination time,number of buttons, the initial selection button number, forcibleexecution button number and the like of the highlight information; aP_PCI button color information table (P_BTN_COLIT) describing buttoncolor information; and a P_PCI button information table (P_BTNIT)describing the coordinate, magnitude, operation mode and the like of thebutton. Since the P_VOBU includes one video frame as described above,the P_PCI_HL_GI is described so that the start time of the highlightinformation indicates 0 and the termination time indicates infinity.

The P_PCI recording information includes a P_PCI video ISRC code(P_ISRC_V) describing an ISRC code of the video of the P_VOBU; and aP_PCI sub-picture ISRC code (P_ISRC_SP) describing an ISRC code of thesub-picture of the P_VOBU.

FIG. 42 shows a structure of the P_DSI information described in theP_DSI packet. The P_DSI includes only the P_DSI general information(P_DSI_GI). The P_DSI general information includes P_VOBU_NV pack time(P_NV_PCK_SCR) corresponding to the least significant 32 bits of the SCRof the NV pack of the P_VOBU, a P_VOBU termination address describingthe relative address with respect to the NV pack of the final pack ofthe P_VOBU, and a P_VOBU first reference address (P_VOBU_1STREF_EA)describing the relative address with respect to the NV pack of the packincluding the final data of the first I picture of the video of theP_VOBU. Since the P_VOBU includes 1 VOBU, the P_NV_PCK_SCR is always 0.

FIG. 29 shows the relationship among the PGC, audio program, cell,picture program, picture cell, AOB, and P_VOB. The entirety of FIG. 29represents one PGC. A plurality of such PGCs are included in one ATS. Asdescribed above, a PGC includes audio programs describing thereproduction order by the audio data access unit and picture programsdescribing the reproduction order by the video data access unit. Eachaudio program has a cell, which is the minimum management unit. The cellpoints to an AOB which is actual audio data and thus determines thereproduction data. In a similar manner, each picture program has apicture cell, which points to a P_VOB, which is actual video data, anddetermines the contents to be reproduced.

Due to such a structure, actual reproduction data pieces can be recordedon the disk in a different order. Alternatively, the same data piece canbe pointed by a plurality of cells or picture cells. In order toguarantee the reproduction continuity, the audio data pieces has a flagwhich indicates whether the physical layout of the data on the disk iscontinuous or the data is a continuous part of one AOB (i.e., audioprogram physical allocation information, audio program time attributeinformation). The video data is fundamentally a still picture.Accordingly, one video data program includes one cell, and one cellincludes one P_VOB. The physical arrangement of the P_VOBs causes nospecific problems. Thus, the video data does not have such a flag.

FIG. 30 shows an exemplary PGC forming a title. The example shown inFIG. 30 includes five programs. Programs #1 and #2 correspond to AOB #1,and programs #3, #4 and #5 correspond to AOB #2. On the recordingmedium, AOB #1 is recorded after AOB #2. Programs #1 and #2 both includea silent cell and a silent cell, and program #2 includes two audiocells. Programs #3 and #4 include a silent cell, and program #5 includesonly an audio cell.

In the case where all the audio cells each have a reproduction timeperiod of 60 seconds (5,400,000 in PTS) and all the still picture cellseach have a reproduction time period of 1 second (90,000 in PTS), audioprogram information can be described as shown in FIG. 32. Pictureprogram information can be described as shown in FIG. 33. Under theconditions that the audio data is 48 kHz, 16 bit sampling with 2channels, the number of the silent packs is 96 and the number of theaudio cell packs is 5760 as shown in FIG. 34. Where the number of stillpicture packs is 50, the picture cell information is as shown in FIG.35. In such a case, it is assumed that the P_VOB used in the picturecell is recorded at a position following an AOB. The recording positionsfor the P_VOB and AOB are not physically limited, and the P_VOB and AOBcan be positioned in a mixed state with no specific problem. In such acase, the physical allocation of the audio program information ofno-Continue indicates that the AOB indicated by the audio program is notcontinuously reproducible. The audio cell and the picture cell bothshare the AOBs and P_VOBs used by the other cells.

The audio title set has been described. Next, with reference to FIG. 22,the audio manager will be described.

(3.2) Data Structure of the Audio Manager 900

The audio manager 900 is information for controlling the reproductionwhich is to be first referred to for performing audio-orientedreproduction of the information on the optical disk by a reproductionapparatus.

FIG. 22 shows a data structure of the audio manager 900.

The audio manager 900 includes “audio manager information (AMGI)”, “VOBfor audio manager menu (AMGM_VOBS)”, and “audio manager informationbackup (AMGI_BUP)” as in the first example.

The “audio manager information (AMGI)” includes “audio managerinformation management table (AMGI_MAT)” including attribute informationand pointer information, “audio title management information” indicatingthe number of audio titles and the like, “audio title search pointer(ATT_SRP)” indicating search information on the audio titles, and “audiomanager menu PGC management information table (AMGM_PGCI_UT)” indicatingPGC information for audio manager menu, as in the first example.

The “audio manager information management table (AMGI MAT)” includes anAMG identifier (AMG_ID) for identifying an audio manager, an AMGtermination address (AMG_EA) which is a termination address for tablemanagement, an AMGI termination address (AMGI_EA), an AMGI_MATtermination address (AMGI_MAT_EA), address information on the AMG andAMGI tables, version number (VERN), a volume set identifier (VLMS_ID), anumber of title sets (TS_Ns) indicating the number of the title setsincluded in the volume, a provider identifier (PRV_ID) for identifyingthe provider which produced the disk, an automatic execution flag(Auto_Play_Flag) defining the operation of the player when the disk isinserted, and AMGM_VOBS indicating VOB attribute information existing inthe audio manager.

The “audio title search pointer table (ATT_SRP)” has an identicalstructure with that in the first example.

The audio zone region and the DVD as a multimedia optical disk have beendescribed. Next, a reproduction apparatus, according to the presentinvention, for reproducing a media having the above-described structurewill be described.

The basic structure of the reproduction apparatus is similar to thestructure described in the first example. In the second example, a keyfor separately controlling audio data and video data is provided in aremote controller for operating the DVD player or a front panel of theDVD player. With such a key, the video data can be skipped forward andbackward or rewound to the start of the video data while continuouslyreproducing the audio data.

FIG. 26 is a block diagram illustrating an internal structure of a DVDplayer 80 in the second example. The DVD player 80 is different from theDVD player 70 shown in FIG. 8 in the structure of the AV decodersection, which will be described below.

In the second example, there are two streams, which are an AOB as audiodata and P_VOB as video data. An AV decoder section 85 a includes twodecoders respectively corresponding to the AOB and P_VOB. These decodersare operated synchronously with or asynchronously from each other.Specifically, the AV decoder section 85 a includes a P_VOB systemdecoder 103 for receiving a P_VOB stream and distinguishing a stream IDand sub-stream ID in a header of each packet included in the stream,thereby classifying the data into a video packet, a PCI packet, and asub-picture packet. The AV decoder section 85 a further includes an AOBsystem decoder 104 for receiving an AOB stream and classifying the dataon a packet header-by-packet header basis. The AV decoder section 85 astill further includes a highlight buffer 94 for temporarily storinghighlight information of a PCI packet from the P_VOB system decoder 103,a video buffer 96 for temporarily storing a video packet in a similarmanner, a sub-picture buffer 105 for temporarily storing a sub-picturepacket, an audio buffer 99 for temporarily storing an audio packet fromthe AOB system decoder 104, a highlight decoder 95 for decoding thehighlight information from the highlight buffer 94 and outputting thedecoded highlight information to the system control section 93, a videodecoder 87 for decoding the video data from the video buffer 96, asub-picture decoder 98 for decoding the sub-picture data from thesub-picture buffer 105, an audio decoder 100 for decoding the audio datafrom the audio buffer 99 and outputting the decoded audio data as anaudio output, a video synthesizer 101 for synthesizing the decodingresults of the video decoder 87 and the sub-picture decoder 98 into onepiece of video data, and a synchronization adjusting section 102 formanaging the synchronization of the highlight decoder 95, the videodecoder 87, the sub-picture decoder 98 and the audio decoder 100.

The reproduction apparatus according to the present invention operatesin, for example, the following manner. The operation up to the readingof the stream is the same as described in the first example and will notbe described below.

For starting the reproduction, the system control section 93 determineswhether or not the DVD player 80 is in a video-oriented reproductionmode, by a reproduction mode determination section. When it isdetermined that the DVD player 80 is in the video-oriented reproductionmode, the system control section 93 reads the video manager based on theinformation which is read from the volume file management region. Thesystem control section 93 refers to the PGC management information tablefor the video manager menu to calculate the recording address of the PGCfor the volume menu. The resultant PGC is reproduced and retainedinside. When the PGC for the volume menu is retained inside, the systemcontrol section 93 refers to the retained PGC information to calculatethe video object (VOB) to be reproduced and the recording address of theVOB on the optical disk. When the VOB to be reproduced is determined,the system control section 93 outputs a control signal to the mechanismcontrol section 83 and the signal processing section 84 so as toretrieve the determined VOB from the optical disk for reproduction.Thus, the video menu from which the user can select the title to bereproduced is displayed (see FIG. 40).

The user sees the menu and selects and confirms the title that he/she isinterested in by designating the item number in the menu using theremote controller. Then, the system control section 93 receives thedesignation of the item number in the menu from the remote controllerand refers to the management information pack included in the VOB of thevideo menu which is being reproduced, the VOB being input from the AVdecoder section 85 a, to execute a control command corresponding to thedesignated number. The control command is PlayTitle #n or the like, andthe title number to be reproduced is designated by “n”. As an executionoperation by the PlayTitle command, the system control section 93 refersto the title search pointer table, which is a part of the audio manager,to determine the audio title set (ATS) to which the designated titlebelongs to and the title number in the ATS. When the ATS is confirmed,the system control section 93 outputs a control signal to the mechanismcontrol section 83 and the signal processing section 84 so as toreproduce the ATS management information of the confirmed title set andretrieves the title search pointer table of the ATS, which is a part ofthe ATS management information, to the system control section 93. Whenthe title search pointer table is retrieved, the system control section93 refers to the table to determine the PGC information for starting thereproduction of the title to be reproduced. When the PGC information isdetermined, the system control section 93 outputs a control signal tothe mechanism control section 83 and the signal processing section 84 soas to reproduce the determined PGC information and retain theinformation in the inside buffer memory for the PGC information. Whenthe PGC information is retained, the system control section 93 firstrefers to the ATS picture program information table, with reference tothe retained PGC information, to read all the P_VOBs described in thePGC information and inputs the P_VOBs to the AV decoder section 85 a.The AV decoder section 85 a separates the input P_VOBs on a pack-by-packbasis or packet-by-packet basis by the P_VOB system decoder 103 andstores the P_VOBs in corresponding buffer memories.

At this point, the highlight decoder 95, the video decoder 87, and thesub-picture decoder 98 do not perform decoding operations. When all theP_VOBs are stored in the corresponding buffer memories, the AOB to bereproduced and the recording address thereof are determined by the ATSprogram information table and the ATS cell reproduction informationtable. Then, the AOB is reproduced by a control signal output to themechanism control section 83 and the signal processing section 84 fromthe system control section 93. At this point, the highlight decoder 95,the video decoder 87, and the sub-picture decoder 98 perform decodingoperations for the first time to start video output, highlightprocessing and audio output. The output timing is adjusting by thesynchronization adjusting section 102 in accordance with the audioprogram information, picture program information, highlight informationand time code information (PTS) of each packet.

In the second example, data for the corresponding picture programs isall stored in the corresponding buffers before the audio data isreproduced. Accordingly, the highlight buffer 94, the video buffer 96,and the sub-picture buffer 105 in the DVD player 80 in the secondexample require a larger buffer memory capacity than the capacityspecified by MPEG2 or DVD-Video.

Thereafter, the system control section 93 sequentially determines theAOBs to be reproduced and controls the reproduction thereof inaccordance with the retained PGC information, and also decodes thehighlight information, sub-picture information and video informationwhich are already read in the buffer memories. When the reproduction ofthe final AOB indicated by the PGC information is completed, the systemcontrol section 93 searches for the PGC information of the next titleand reproduces the P_VOBs and the AOBs described in the PGC informationin the same manner.

Thus, the all the titles are reproduced and the operation is stopped. Inaccordance with specific setting of the DVD player or the DVD, only onetitle can be reproduced before the operation is stopped, or a menu canbe displayed after reproduction of one or more titles is completed.

Next, a method for reproducing a still picture cell, a silent cell andan audio cell will be described in detail.

FIG. 14 shows a conventional method for reproducing the audio cell.Conventionally, for reproducing an MPEG2 stream, the leading end of theaudio cell pack is first sought by the optical head and data readingstarts. However, audio output does not immediately start but startsafter an idle time period, which is predetermined in each reproductionapparatus. The idle time period includes a time period required fordetermining the PTS of the audio data, a time period required fordetermining that data is correct, and a time period required for themuting circuit in an analog output section is to be transitioned from amute state to a non-mute state. Thus, the idle time period varies inaccordance with the type of reproduction apparatus. Especially when thereproduction section and the decoder are accommodated in separatechassis, the idle time period tends to be extended because determinationon the PTS and the determination on the correctness of the audio dataare separately performed.

FIGS. 36A and 36B show methods for reproducing a silent cell and anaudio cell. FIG. 36A shows the method in the case where the reproductionis performed from the leading end of the data, and FIG. 36B shows themethod in the case where the reproduction is performed in continuationfrom the previous cell.

In the case where reproduction is performed from the leading end of thedata by selecting a title or program from the menu or the like throughjumping, the leading pack of the silent cell is jumped to with referenceto the start address of the cell information. At this point, the STC,which is the reference time of the decoder, is set with the SCR of theleading pack of the silent cell. Next, skipping and jumping of datacorresponding to a prescribed idle time period are performed withreference to the PTS of the silent cell, and the silent cell for theidle time period is reproduced. Audio output is prepared for during thisperiod. At this point, the next title number is not displayed on thedisplay device of the reproduction apparatus, and the passage ofreproduction time period is not updated. In the case where the audiooutput is started and display of the title number and the updating ofthe passage of the reproduction time period are performed simultaneouslywhen the first PTS of the leading cell is detected, the reproductionapparatus behaves as if the audio data is output simultaneously with thecompletion of the jump such as menu selection.

In the case where the reproduction is performed in continuation from theprevious cell, a silent cell is jumped over or skipped except for theidle time period. At this point, by continuously counting the STC, whichis reference for the system time, the interval between the completion ofthe audio output by the previous cell and the start of the audio outputby the next cell equals the audio pause time period. The counting of theSTC is continued when the physical allocation information and the timeattribute information both have a value indicating “continue”. Wheneither one of them indicates “no-continue”, the same processing as inthe jump from the menu is performed, and thus the STC is reset at theleading end of the silent cell pack. In the case where there is nosilent cell and the reproduction starts from the leading end of thedata, the operation is similar to the conventional operation shown inFIG. 14. In the case where the reproduction is performed in continuationfrom the previous cell, the operation is as follows. When the timeattribute information indicates “continue”, the audio cell is decodedcontinuously from the previous cell and audio data is output. When thetime attribute information indicates “no-continue”, the operation is thesame as the conventional operation shown in FIG. 14 as in the case wherethe reproduction is performed from the leading end of the data.

FIGS. 37 through 39 are flowcharts each illustrating a program. Sinceinformation on the P_VOBs is read in the corresponding buffer memories,reproduction of the audio data and processing of the highlightinformation can be performed asynchronously from each other, and thestill picture and the sub-picture can be output asynchronously from eachother. Needless to say, synchronous display is possible based on thetime code or the time information of the system.

Regarding reproduction of audio information, in the case where thephysical allocation information of the audio program information shows“continue” and the program previously reproduced has a program numberwhich is smaller by one than the program number of the program to bereproduced now, seek to the reading head for the DVD is not specificallynecessary. When the time attribute information indicates “continue” andthe reproduction is performed in continuation from the previous program,the STC, which is the reference time for the decoder, does not need tobe reset.

The determination of whether or not the cell is a silent cell isperformed using the cell type in the cell information. The determinationthat the cell is the final cell is performed by comparing thetermination address of the cell information and the address read fromthe data in the DVD. The completion of the reproduction of the audioprogram can be determined by the cell index of the cell informationreturning to zero, the cell type indicating a still picture cell or asilent cell, or the start cell number of the next program in the audioprogram information.

The skipping of the silent cell is performed while detecting the PTSwhen the silent cell is decoded or by obtaining the number of packs tobe skipped based on the data rate.

Since data of a still picture is already stored in the buffer memory,the display of the still picture is managed based on the position in thebuffer memory at which the still picture of the designated cell of thedesignated program is recorded or based on the ordinal number (i.e.,first, second, etc.) of the still picture with respect to the start.When the management is performed based on the position in the buffermemory, the data is sent to the video decoder 87 from the designatedaddress in the video buffer 96 and displayed. When the management isperformed based on the ordinal number of the still picture, the datastored in the video buffer 96 from the leading end thereof is sent tothe video decoder 87 and the display is switched when the designatedordinal number is reached. The transmission of the data is stopped atthis point. The display time period of the still picture is inaccordance with the description in the picture cell still time(P_C_Still_Time). Since still pictures are each 1-frame data, thepresent still picture is switched into the next still picture when thetime period described in the picture cell still time has passed. Suchcontrol is usually performed by the system control section 93. A picturecell still time of FFh indicates infinity, which means that the stillpicture is switched basically only by a command, user operations, orcompletion of the audio program. When the still picture is switched,display effects can be added by designating the transition mode. Thetime to switch the still picture can be designated on aprogram-by-program basis before and after the display of the stillpicture. However, in the case where the reproduction apparatus does nothave a special effect display function, the still picture can simply beswitched with the display effects being ignored.

In a synchronous mode, the audio data is reproduced based on the audioprogram reproduction time period and the time code information of theaudio data, and the still picture and the sub-picture are reproducedbased on the picture program reproduction time period. Thesynchronization adjusting section 102 compares the reference timeinformation of the system and the reproduction time periods and thusperforms synchronization control.

In an asynchronous mode, audio data is not synchronized with andreproduced separately from highlight data, sub-picture data and stillpicture data. The highlight data, sub-picture data and still picturedata are synchronized to one another, and the audio data is continuouslyreproduced realtime based on the time information of the system. Thestill picture is switched in the asynchronous mode by the useroperations and the command. The user operations basically include anoperation of continuously reproducing audio programs while feedingpicture programs forward, backward or to the leading end; and anoperation of feeding both audio programs and picture programssimultaneously forward, backward or to the leading end. The command hassimilar functions.

The synchronous mode and the asynchronous mode are switched over inaccordance with the picture program reproduction control. In the casewhere the picture program reproduction control is designated so as toprohibit control by the user operations, the data is basicallyreproduced in the synchronous mode except for by the command.

In the case where the picture program reproduction mode prevents theuser operations and command from synchronizing audio programs andpicture programs with each other, the DVD player can wait until thesynchronization is obtained or the picture programs can be continuouslyreproduced in accordance with the picture program reproduction timeperiod without synchronization. In the case where the reproduction ofthe audio programs is not completed when the reproduction of the pictureprograms is completed, the picture programs can be continuouslyreproduced from the first picture program or the final picture programcan be continuously reproduced. In the case where the reproduction ofall the picture programs are completed before all the audio programs arecompleted, only the picture programs can be reproduced with the audiopart being silent, the audio programs can be reproduced from the firstaudio programs, or the reproduction of the audio title can beterminated. Some of the audio programs and the picture programs includedin the audio title can be randomly selected and repeated a designatednumber of times. Such audio and picture programs can be repeated so thatno same program is repeated (shuffle mode). The audio programs and thepicture programs are synchronized to each other so that the audioprogram and the picture program having the same number can be alwaysreproduced simultaneously, or the audio programs and the pictureprograms can be reproduced independently and asynchronously.

An audio title number or time can be directly designated forreproduction by user operations, i.e., usually by a remote controller orother keys. Such reproduction by direct designation by user operationscannot be used when the directly designated reproduction prohibitionflag (UOP1) and the time designated reproduction prohibition flag (UOP2)of the ATT_CAT indicate prohibition. By such a designation, the titlecreators can describe reproducible audio titles by a command under someconditions of the reproduction apparatus. For example, an audio titlewhich is not usually reproducible can be reproduced under certainconditions. For example, a certain parameter can be set in a specificplayers so that the parameter can be evaluated by a command, and thecommand can be described so as to reproduce the audio title only when avalue is set in the parameter. When UOP1 and UOP2 are set so as toprohibit directly designated reproduction, the audio title can bereproduced only by the specific player. Such a system easily allowsreproduction of certain audio titles, recorded on a disk including aplurality of audio titles, for which fee has been paid.

AV decoder sections having other structures are usable. For example, asshown in FIG. 27, an AV decoder section 85 b also acts as a systemdecoder for AOB and P_VOB. Since the AOB and P_VOB are input atdifferent timing, the same type of AV decoder section as used byDVD-Video is usable except that the capacities of the highlight buffer94, the video buffer 96, and the sub-picture buffer 105 are increasedand that a still picture management mechanism is added to the control ofthe video buffer 96. The operation of the AV decoder section 85 b issubstantially the same as that of the AV decoder section 85 a.

The DVD player can have the structure shown in FIG. 28. In thisstructure, a P_VOB buffer 106 for P_VOB streams is provided immediatelybefore the AV decoder section 85 b. The same type of AV decoder sectionas used by DVD-Video is usable. All the P_VOB data to be read before thereproduction of the audio data is stored in the P_VOB buffer 106. TheP_VOB buffer 106 dynamically multiplexes the P_VOBs corresponding to thereproduction order with the audio stream and sends the resultant data tothe AV decoder section 85 b. Accordingly, the system decoder 120 for AOBand P_VOB in the AV decoder section 85 b is required to have aprocessing speed which is slightly higher than the speed specified bythe DVD-Video standards. Streams need to be supplied to the AV decodersection 85 b so that the audio buffer 99 does not underflow.

In the second example, as described above, program reproductioninformation including the start time and reproduction time period ofeach piece of audio data based on the reproduction start time of theleading audio data in the MPEG2 stream is recorded in the managementregion as a part of the reproduction control information. Accordingly,an optical disk for realizing reproduction of high quality digital audiodata along with the video data in a restricted range of bit rates isprovided. Moreover, a certain interval between audio reproductions canbe maintained even in an inexpensive reproduction apparatus including novideo data reproduction function. This allows title creators to createdata easily.

Since a plurality of still pictures, sub-picture and menu can bedisplayed synchronously with or asynchronously from high quality audiodata, a wider variety of displays become available.

Example 3

An optical disk, and an apparatus and method for reproducing informationfrom the optical disk in a third example according to the presentinvention will be described. Identical elements previously discussed inthe first example bear identical reference numerals and the descriptionsthereof will be omitted.

(1) Physical Structure of the Optical Disk

The physical structure of the optical disk is identical with thatdescribed in the first and second examples and thus the descriptionthereof will be omitted.

(2) Logical Structure of the Optical Disk

The logical structure of the optical disk is identical with thatdescribed in the first and second examples and thus the descriptionthereof will be omitted.

(3) Data Structure of the Audio Zone Region 32 c

FIG. 43 shows a data structure of the audio zone region 32 c. The audiozone region 32 c stores an audio manager 900 and one or more audio titlesets 800 as in the first and second examples. The audio zone region 32 cfurther stores an audio still video set 1100.

(3.1) Data Structure of the Audio Manager 900

FIG. 44 shows a data structure of the audio manager 900 in the thirdexample. The structure of the audio manager 900 has the same structureas that shown in FIG. 4 down to the stage of the audio managerinformation management table (AMGI_MAT) 902.

The audio manager information management table 902 includes an ASVSstart address (ASVS_SA) 904 for storing the position of the audio stillvideo set.

The structure of the audio manager information management table 902 isthe same as that shown in FIG. 22 except for the ASVS start address 904.

(3.2) Data Structure of the Audio Still Video Set 1100

FIG. 45 shows a data structure of the audio still video set 1100. Theaudio still video set 1100 includes a plurality of picture video objects(hereinafter, referred to as “P_VOBs”) 1102, audio still video setmanagement information (ASVSI) 1101 for managing the plurality of P_VOBs1102, and audio still video set management information backup(ASVSI_BUP) 1103. In the following description, the audio still videoset will generally be referred to as an “ASVS”. The P_VOBs 1102 willgenerally be referred to as an “audio still video object (ASVOB)”.

(3.2.1) Data Structure of the P_VOB 1102

FIG. 46 shows a data structure of the P_VOB 1102. The P_VOB 1102includes a picture NV pack (P_NV_PCK) 1113, a plurality of video packs(V_PCK) 1114, and a plurality of sub-picture packs (SP_PCK) 1115. Onlyone picture NV pack 1113 is included in each P_VOB 1102.

The video packs (V_PCK) 1114 each stores video data forming anMPEG-system I picture. Unlike the VOB, the P_VOB is for storing a stillpicture but not a moving picture. Accordingly, the video data stored ineach video pack 1114 includes only an I picture which isin-frame-compressed. Herein, information indicating one still picturecorresponds to one I picture.

The sub-picture packs 1115 can each store a plurality of sub-picturestreams. Each sub-picture packs 1115 stores an identification code foridentifying the plurality of sub-picture streams. The sub-picture packs1115 need not be included in the P_VOB 1102.

The picture NV pack 1113 includes a DSI packet (not shown) and a PCIpacket (not shown). The DSI packet stores information used for specialeffects such as fast-forward reproduction. The PCI packet storeshighlight information 1120 (FIG. 47).

As shown in FIG. 47, the highlight information 1120 includes ASVhighlight general information 1121 indicating an effective period, thenumber of buttons, and the like of highlight; ASV button colorinformation 1122 indicating the display color of the button; and an ASVbutton information table 1123 indicating a button command and the like.

Unlike in the case of DVD-Video, the P_VOB 1102 does not have any audiodata.

(3.2.2) Data Structure of the Audio Still Video Set ManagementInformation 1101

As shown in FIG. 45, the audio still video set management information1101 includes audio still video unit information (ASVUI) 1131 formanaging a plurality of still pictures as a group and an audio stillvideo search pointer table (ASV_SRPT) 1132 for managing the recordingposition of the P_VOB 1102.

The audio still video unit information 1131 is information for managinga plurality of P_VOBs 1102 having the same attribute and continuouslyrecorded on the disk. Such information is a basic unit for reproductionprocessing.

The audio still video unit information 1131 includes an “audio stillvideo set ID (ASVS_ID)”; a “number of audio still video sets (ASVS_Ns)”;a “P_VOB start address (P_VOBS_SA)” and a “P_VOB termination address(P_VOBS_EA)” indicating the recording position of the P_VOB; an “ASVUattribute” indicating the ASVU attribute such as, for example, acompression method of the P_VOB, aspect mode and existence of a button;a “P_VOB sub-picture palette (P_VOBS_SP_PLT)” for determining thedisplay color of the sub-picture; and “ASVU general information(ASVU_GI)” corresponding to each ASVU for designating the P_VOBbelonging to each ASVU.

Each “ASVU general information (ASVU_GI)” includes a “number of P_VOB(P_VOB_Ns)” indicating the number of P_VOBs forming the ASVU, and a“start P_VOB number” indicating which P_VOBs belong to the ASVL.

The audio still video search pointer table 1132 stores a plurality of“ASV search pointer (ASV_SRPT)” indicating the start address of each ofthe P_VOBs included in the ASVS.

(3.3) Data Structure of the Audio title Set 800

FIG. 48 shows a data structure of the audio title set 800 in the thirdexample. The audio title set 800 shown in FIG. 48 has the same structureas that shown in FIG. 5 except for the structure of the PGC information833.

FIG. 49 shows a data structure of the PGC information 833. The PGCinformation 833 includes “ATS PGC general information (ATS_PGC_GI)”, an“ATS program information table (ATS_PGIT)”, an “audio cell reproductioninformation table (ATS_C_PBIT)”, and an “ATS audio still videoreproduction information table (ATS_ASV_PBIT)”.

The “ATS PGC general information (ATS_PGC_GI)” includes the number ofaudio programs and the number of cells included in the PGC information;the reproduction time period of the PGC; and information the ATS_PGCinformation. The address information on the ATS_PGC information includespointer information to an “ATS program information table (ATS_PGIT)”, an“audio cell reproduction information table (ATS_C_PBIT)”, and an “ATSaudio still video reproduction information table (ATS_ASV_PBIT)”.

The “ATS program information table (ATS_PGIT)” includes a plurality“audio program information (ATS_PGI)” units included in the PGC.

Each of the plurality of “audio program information (ATS_PGI)” unitsincludes “audio program physical allocation information” indicatingwhether or not the AOB of each program and the AOB of the previousprogram are recorded at physically discontinuous positions on theoptical disk, “audio program time attribute information” indicatingwhether or not the time information of the AOB is continuous with thetime information of the previous AOB, an “audio program start cellnumber” indicating the first cell number forming the audio program,“reproduction start audio cell time” indicating the first timeinformation of the first audio cell included in the audio program, an“audio program total reproduction time period” indicating thereproduction time period of the audio program, an “audio pause timeperiod” indicating the silent period until the reproduction of the audiocell of the audio program starts, an “ASVU number (ASVUN)” designatingthe still picture unit to be reproduced simultaneously with audio dataof the program, an “audio still video display mode (ASV_DMOD)”indicating the display mode of the still picture such as, for example,whether the still picture or still pictures are displayed in accordancewith the order or randomly, and an “ATS_ASV_PBI start address” and“ATS_ASV_PBI termination address” designating corresponding ATS audiostill video reproduction information in the ATS audio still videoreproduction information table (ATS_ASV_PBIT).

FIG. 50 shows a data structure of the “audio still video display mode(ASV_DMOD)”. The “audio still video display mode (ASV_DMOD)” includes a“display timing mode” flag and a “display order mode” flag.

The “display timing mode” indicates specific timing for reproducing theaudio data and an updating time period of the still picture.

When the “display timing mode” is Browsable, the display timing of thestill picture can be changed by interaction from the user. When the“display timing mode” is SlideShow, the display timing of the stillpicture cannot be changed by interaction from the user.

When the “display timing mode” is SlideShow, the display of the stillpicture is updated in accordance with the display timing determinedsynchronously with the audio information which is simultaneouslyreproduced. When the “display timing mode” is Browsable, the display ofthe still picture is updated when the determined display continuationtime period has passed, asynchronously from the audio information whichis simultaneously reproduced.

The “display order mode” indicates whether the still picture or stillpictures are displayed sequentially in accordance with the display list,randomly or shuffle. A random display of the still picture refers tothat the still picture or still pictures are selected randomly whilepermitting overlap and are displayed in conformity with the selectedorder. A shuffle display of the still picture refers to that the stillpicture or still pictures are selected randomly while prohibitingoverlap and are displayed in conformity with the selected order.

The “audio cell reproduction information table (ATS_C_PBIT)” includes aplurality of “audio cell reproduction information (ATS_C_PBI)” units.Each “audio cell reproduction information unit (ATS_C_PBI)” includes a“cell index number” indicating the order of cells included in theprogram, a “cell type” indicating the attribute of the cell (i.e.,whether the cell is a still picture cell or a silent cell), a “cellstart address” indicating the start address of the cell in the form of arelative address with respect to the first pack of the AOB of the ATSincluding the cell, and a “cell termination address” indicating thefinal address of the cell in the same manner.

The “ATS audio still video reproduction information table(ATS_ASV_PBIT)” includes a plurality of “ATS audio still videoreproduction information (ATS_ASV_PBI)” units. Each “ATS audio stillvideo reproduction information unit (ATS_ASV_PBI)” includes a pluralityof “display lists (DLIST)” indicating which P_VOBs stored in the audiostill video set are reproduced and in which order the P_VOBs arereproduced.

Each “display list (DLIST)” includes an “ASV number” indicating theordinal number (i.e., first, second or the like) of the P_VOB in theASVU, an “initial button number (FOSL_BTNN)” indicating the number of abutton which is in the highlight information and selected in an initialstate, an “audio program number” indicating the audio programcorresponding to the DLIST, “display timing” indicating the timing fordisplaying the P_VOB included in the DLIST, and a “start sectiontransition mode” and a “termination section transition mode” indicatingthe transition of the still picture.

In this example, as the picture transition modes, “no transition”,“fading from black”, “fading into black”, “cross-fading”, and “wiping inseveral directions” are assumed.

(3.4) Data Structure of the AOB 802

The AOB 802 is packetized into 2 Kbytes. The AOB 802 stores data in theLPCM format, AC3 format, DTS format or other compression formats. In thecase of the LPCM format, the sample bit is 16, 20, or 24 bits, with asampling frequency of 48 kHz, 96 kHz, 192 kHz, 44.1 kHz, 88.2 kHz, or176.2 kHz.

The AOB 802 has an exemplary structure as described in the secondexample with reference to FIG. 24.

(4) Two Reproduction Methods

The audio zone region 32 c stores three MPEG streams of a VOB, an AOBand a P_VOB. The AOB is included in the audio title set (ATS). The P_VOBis included in the audio still video set (ASVS). The VOB is included inthe audio manager (AMG) as shown in FIG. 44.

The AOB and the P_VOB are the main information stored on the disk, andare typically music information with a still picture. The VOB istypically a menu for allowing the user to select any music informationwith a still picture.

Among the MPEG streams stored in the audio zone region 32 c, the VOB isreproduced by a standard method specified by MPEG. The AOB and the P_VOBare reproduced by an expanded different method which is different fromthe standard method.

(4.1) Standard Reproduction Method

First, the standard reproduction method will be described. This methodis used for reproducing a VOB stored on the optical disk.

FIG. 51 shows a data structure of a system stream in the third exampleconforming to MPEG. The optical disk stores at least one system stream.

The system stream can include a plurality of elementary streams. Theelementary streams include a video elementary stream storing movingpicture information, an audio elementary stream storing audioinformation, and a sub-picture elementary stream storing sub-pictureinformation. The plurality of elementary streams are each divided into aplurality of packs.

The system stream shown in FIG. 51 includes a video elementary stream,an audio elementary stream, and a sub-picture elementary stream. Thevideo elementary stream is divided into one or more video packs. Theaudio elementary stream is divided into one or more audio packs. Thesub-picture elementary stream is divided into one or more sub-picturepacks. In FIG. 51, the letter “V” represents a video pack, the letter“A” represents an audio pack, and the letter “S” represents asub-picture pack.

As shown in FIG. 51, each pack includes a “pack header”, a “packetheader” and a “data field”. The data length of one pack is 2 Kbyte.

Described in the “pack header” is data conforming to MPEG including, forexample, a pack start code, an SCR (System Clock Reference), and an MUX(Multiplex) rate.

Described in the “packet header” is data confirming to MPEG including,for example, a stream ID, a packet length, an STD (System TargetDecoder), a buffer scale size, and a PTS (Presentation Time Stamp).

The stream ID described in the “packet header” indicates whether datastored in the “data field” is a video elementary stream or any otherelementary stream. Any other elementary stream is an audio elementarystream, a sub-picture elementary stream or management information.

The management information is referred to as an “NV pack”. Themanagement information includes a PCI packet and a DSI packet. The PCIpacket stores highlight information for receiving and processing userinteraction. The DSI packet stores information utilized for specialeffects such as, for example, fast-forward reproduction.

In this example, the data field of the elementary streams other than themanagement information stores a sub-stream ID. The sub-stream ID is an8-bit field indicating whether the data stored in the data field isaudio data or sub-picture data. The sub-stream ID further indicates anencode type and a channel identification number. When the data stored inthe data field is audio data, the encode type is one of the linear PCMformat, AC-3 format, DTS format and the like, and the channelidentification number is one of #0 through #7 (8 types max.). When thedata stored in the data field is sub-picture data, the channelidentification number is one of #0 through #31 (32 types max.).

In the “data field”, data compressed in accordance with a prescribedformat is recorded. For example, video data is compressed by MPEG2 andrecorded in the data field. Audio data is compressed by the linear PCM,AC-3 or DTS format and recorded in the data field. Sub-picture data iscompressed by the run-length coding and recorded in the data field.

The PTS in the “pack header” and the “packet header” is used tosynchronize the decoding of the audio pack and the decoding thesub-picture pack.

In the case where the reproduction apparatus reproduces a system streamrecorded on the optical disk, the reproduction apparatus sets the SCRincluded in the leading pack of the system stream as an initial value ofthe STC, which is a reference clock, and inputs each pack to thecorresponding decoder at time timing indicated by the SCR whilereferring to the STC. Each of the decoded packs is externally outputfrom the decoder at the timing indicated by the PTS. By outputting eachpack at the timing indicated by the PTS included in the pack, thesynchronization of the audio, video and sub-picture outputs isguaranteed.

As described above, in the case of using the standard reproductionmethod, the system stream to be reproduced is multiplexed with audioinformation, video information and sub-picture information. The systemstreams are reproduced by resetting the STC, which is a reference clock,of each system stream and externally outputting the audio, video andsub-picture data from the decoder at the timing indicated by the PTSincluded in each pack. Thus, the audio data, video data and sub-picturedata are reproduced synchronously with one another.

(4.2) Reproduction Method of AOB and P_VOB

Hereinafter, a reproduction method of an AOB and a P_VOB recorded on theoptical disk will be described.

FIG. 52 shows the relationship among the P_VOB, ASVU, Program and AOB.

An ATS can include a plurality of PGC information (ATS_PGCI) units. Inthe example shown in FIG. 52, the ATS includes one PGC information unit(ATS_PGCI).

Described in the PGC information is one or more audio programinformation (ATS_PGI) units (e.g., Program #1, Program #2, . . . Program#L). The audio program information is an audio data access unit.

The audio program information includes one or more audio cellreproduction information (ATS_C_PBI) units. The audio cell reproductioninformation unit is a minimum management unit. The audio cellreproduction information points to the position in the audio data storedin the AOB. Thus, the audio data to be reproduced in relation to theaudio cell reproduction information is determined.

Also described in the PGC information is one or more ATS audio stillvideo reproduction information (ATS_ASV_PBI) units. The ATS audio stillvideo reproduction information defines the mode in which the stillpicture is reproduced on a program-by-program basis. A plurality ofaudio program information units can share one ATS audio still videoreproduction information unit. In the example shown in FIG. 52, Program#1 and Program #2 share ATS_ASV_PBI#1.

The audio still video reproduction information can be shared when aplurality of audio program information units point to a common entry inthe ATS audio still video reproduction information table (ATS_ASV_PBIT).

FIG. 69 shows the relationship between the DLIST and P_VOB.

The ATS_ASV_PBI includes a plurality of display lists (DLIST),and eachDLIST points to the still picture data (P_VOB) to be displayed. Usually,the still picture data (P_VOB) is reproduced in accordance with theorder of the DLIST. The ATS_ASV_PBI can be designated by the unit of theprogram of the ATS_PGCI. The same ATS_ASV_PBI can be designated bycontinuous programs. The P_VOB can be designated by the ASVU, which is areading unit. The same ASVU is designated by the programs designatingthe same ATS_ASV_PBI.

In other words, continuous programs can be designated so as to use thesame ATS_ASV_PBI with respect to the same ASVU. This is referred to asthe ASVU range.

During the reproduction of the programs in the same ASVU range, the sameASVU is used. Accordingly, the still picture is not read and thus thereproduction of audio data is not interrupted. The DLIST of theATS_ASV_PBI can designate an arbitrary P_VOB which is included in thesame ASVU. Accordingly, the same P_VOB can be designated a plurality oftimes. The P_VOB in the ASVU need not be designated in the DLIST.

Accordingly, different still pictures can be reproduced while using thesame ASVU among different programs, although the ATS_ASV_PBI needs to bechanged.

The audio program information designates the ASVU recorded in the ASVSin order to designate a plurality of still pictures (P_VOB) to bedisplayed simultaneously with the reproduction of the AOB.

The ASVU defines the unit by which the reproduction apparatus buffersthe still picture data. In other words, the still picture data in thedesignated ASVU is read before one audio program information unit isreproduced. Accordingly, the reproduction apparatus need not read thestill picture data from the optical disk while reproducing a musicprogram.

When reproducing the next music program information, the reproductionapparatus determines whether the plurality of pieces of still picturedata indicated by the required ASVU exists in the main memory area ornot. In the case where the plurality of pieces of still picture data ofASVU used in the previous audio program information exist in the mainmemory area, the reproduction apparatus need not read the still picturedata from the optical disk.

The disk title creators can allow the reproduction apparatus to switchfrom one audio program information unit to the next audio programinformation unit rapidly by causing one ASVU to be shared by the twoaudio program information units. The reproduction apparatus can performrapid switching from one audio program unit into the next audio programunit when the successive audio program units share the ASVU.

Each ATS#ASV_PBI manages the display order of the still pictures to bedisplayed by the display list (DLIST). In the display list (DLIST), thestill picture to be displayed is designated by the ASV number. The ASVnumber is used for specifying the still picture included in the ASVU.

Thus, the PGC information allows the still picture to be designated foreach audio program information unit. Alternatively, the same stillpicture can be displayed for a plurality of audio program informationunits. Even when the audio program information is changed, the displaycan be changed without muting the audio data.

FIG. 53 shows an exemplary PGC forming a title. In this example, the PGCincludes f our audio programs. Audio program #1 corresponds t o AOB #1,audio program #2 corresponds to AOB #2, audio programs #3 and #4correspond to AOB #3. On the recording medium, the AOBs are recorded inthe order of AOB#1, AOB#2 and AOB#3. Audio programs #1, #2 and #3 eachhas a silent cell, and audio programs #2 has two music cells.

Audio programs #1 and #2 represent ASVU#1, and audio programs #3 and #4represent ASVU#2. P_VOB #1 is displayed in the cell #2, P_VOB #2 isdisplayed in the cell #4, P_VOB #3 is displayed in the cell #5, P_VOB #4is displayed in the cell #7, and P_VOB #5 is displayed in the cell #8.

In the case where all the audio cells each have a reproduction timeperiod of 60 seconds (5,400,000 in PTS) and all the still picture cellseach have a reproduction time period of 1 second (90,000 in PTS), audioprogram information can be described as shown in FIG. 54. Still pictureprogram information can be described as shown in FIG. 55.

Under the conditions that the audio data is 48 kHz, 16 bit sampling with2 channels, the number of the silent packs is 96 and the number of theaudio cell packs is 5760 as shown in FIG. 56. Where the number of stillpicture packs is 50, the ASV search pointer is as shown in FIG. 57. TheASVU general information is as shown in FIG. 58.

In this example, the address information on the ASV search pointer is arelative address with respect to the recording position of the firstP_VOB, but can be in any other form which specifies the position of theP_VOB on the optical disk. In the case where, for example, the ASVUgeneration information includes address information acting as thereference, the address information of the ASV search pointer can be therelative address with respect to the position indicated by the addressinformation in the ASVU general information.

When the audio still video display mode is “SlideShow” as in the case ofprograms #1 and #2 shown in FIG. 54, the still picture reproduction isreproduced in synchronization with the audio data. Since the ASVU numberof the programs #1 and #2 is “1”, ASVU #1 is read to the buffer beforethe reproduction of the programs. Then, as shown in FIG. 55, the stillpicture information #1 is referred to from the address information ofthe ATS_ASV_PBI to start the display of still pictures in display lists#1, #2 and #3 in the ATS audio still video reproduction information #1at the time indicated by the “audio program number” and “display timing”of the display lists. The display timing is synchronous with thereproduction time period of the audio information to be reproduced withthe still pictures.

More specifically, the still picture in the display list #1 of the ATSaudio still video reproduction information #1 is displayed when the PTSbecomes 90,000 while the AOB #1 is being reproduced. The still picturein the display list #2 of the ATS audio still video reproductioninformation #1 is displayed when the PTS becomes 90,000 while the AOB #2is being reproduced. The still picture in the display list #3 of the ATSaudio still video reproduction information #1 is displayed when the PTSbecomes 5,580,000 while the AOB #2 is being reproduced.

As described above, when the audio still video display mode is“SlideShow”, the still picture is displayed at prescribed timingsynchronously with the reproduction of the audio data. The displaytiming cannot be changed by the interaction from the user (e.g.,selection of a specific button by the mouse).

FIG. 59A shows the relationship between the reproduction timing of theaudio data and the display timing of the still picture when the audiostill video display mode is “SlideShow”.

By contrast, when the audio still video display mode is “Browsable” asin the case of programs #3 and #4 shown in FIG. 54, the still picture isreproduced asynchronously from the audio data. Since the ASVU number ofthe programs #3 and #4 is “2”, the ASVU #2 is read to the buffer beforethe reproduction of the programs. Then, still picture information #2 isreferred to from the address information of the ATS_ASV_PBI. The displaytiming of the still pictures in display lists #1 and #2 in the ATS audiostill video reproduction information #2 can be changed by theinteraction from the user (e.g., input of a command by the user).

In the case where no interaction from the user is generated within theperiod indicated by the “display timing” of the display list, the timeperiod indicated by the “display timing” is considered as the displaycontinuation time period. When the display continuation time period haspassed, the display of the next still picture is started.

It is possible to designate with the audio still video display modewhether the still pictures are sequentially displayed in accordance withthe display list, the still pictures randomly selected while permittingoverlap are reproduced (random reproduction), or the still picturesrandomly selected while prohibiting overlap are reproduced (shufflereproduction).

Practically, when the reproduction starts with program #3, ASVU #2 isloaded to the buffer since the ASVU number of program #3 is “2”. Then,the DLIST indicated by the ATS audio still video reproductioninformation #2 is referred to from the address information of theATS_ASV_PBI. Since the audio program number of display list #1 is “3”,P_VOB #4 corresponding to the ASV number of the display list #1 isdisplayed. When a key corresponding to the Next_DLIST provided on theremote controller is pressed, the still picture of DLIST #2, i.e., P_VOB#5 indicated by the ASV number of DLIST #2 is displayed.

The still pictures in the DLISTs are displayed in accordance with the“display effect” (i.e., the start section display effect and terminationsection display effect, see FIG. 55). When no user operation isperformed within the time of 5,490,000 indicated by the display timingof display list #1, i.e., about 1 minute (matching to the reproductiontime period of program #3), the still picture of the next DLIST, i.e.,P_VOB #5 is displayed in accordance with the “display effect” and the“transition time”. The audio data of program #4 is reproduced inrelation with the display of P_VOB #5.

In the case where the reproduction time period of program #3 is shorterthan the time period indicated by the display timing of P_VOB #4, thedisplay of P_VOB #4 is terminated and the display of P_VOB #5 is startedwhile program #3 is being reproduced. In the case where the display timeperiod indicated by the display timing of P_VOB #4 is longer than thereproduction time period of program #3, the display of P_VOB #5 isstarted after the reproduction of program #4 is started.

When the reproduction is started with program #4, ASVU #2 is read as inthe case of starting with program #3 to display the P_VOB in the firstDLIST having the audio program number of “4”. Thereafter, the display ofthe still pictures can be changed in accordance with the user operationsor command. The audio program number of the DLIST is effective only fordetermining the P_VOB to be displayed first only when the ASVU ischanged. When the reproduction is continued, a user operation or commandhas priority over the audio program number. When the P_VOB is displayedwhile the time period indicated by the display timing, the P_VOBindicated by the next DLIST is displayed.

When the value indicated by the display timing refers to “infinity”, thecorresponding P_VOB is continuously displayed until the user operationor execution of a command is performed. As the value indicating theinfinity, the maximum value (e.g., all the bit values are “1”) can beused but other values are also usable. When the audio still videodisplay mode is “Browsable”, the display time period of the P VOB canalways be infinite.

FIG. 59B shows the relationship between the reproduction timing of theaudio data and the display timing of the still picture when the audiostill video display mode is “Browsable”.

In this example, information required for each audio programs isrecorded in the audio program information (ATS_PGI). When theinformation is found to correspond to each audio program, theinformation can be recorded in any area. For example, as shown in FIG.60, the ASVU number, audio still video display mode, ATS_ASV_PBI startaddress, and ATS_ASV_PBI termination address are recorded in the audiostill video reproduction information search pointer(ATS_PG_ASV_PBI_SRP).

As described above, the AOB and P_VOB are reproduced simultaneously bydecoders unlike in the case of the VOB.

Hereinafter, the reproduction method of the VOB and the reproductionmethod of the AOB and P_VOB will be compared.

The two reproduction methods are identical with each other in that videoinformation is output along with the audio information. It should benoted that in the case of the P_VOB, the video information is stillpicture information including an I picture.

One difference between the two reproduction methods is the recordingposition of the data. In the case of the VOB, audio information andvideo information are multiplexed together and recorded on the opticaldisk as one system stream, whereas the AOB and the P_VOB are recorded indifferent areas of the optical disk as different system streams.

Another difference between the two reproduction methods is thesynchronization method of audio data and still picture data. VOBs arereproduced by a decoder one by one as described above. In more detail,the STC, which is a reference clock, is reset by the SCR in the “packheader”, and the STC is referred to output both audio information andstill picture information at the timing of the PTS in the “packetheader” in each pack. By contrast, AOBs and P_VOBs are reproduced bydecoders simultaneously. As described in more detail below, a pluralityof prescribed P_VOBs to be reproduced synchronously with the AOB areread from the disk and input to the decoder before the AOBs. Unlike theVOBs, the P_VOBs input to the decoder are not displayed immediately butare held in the decoder. Regarding each P_VOB, it is considered that theSTC is reset with the SCR of the leading pack in accordance with theMPEG decoding model and the P_VOB is decoded in accordance with the PTSin the packet, so that data after the plurality of prescribed P_VOBs tobe reproduced synchronously with the AOB is accumulated. Actually, thedata regarding the P_VOB before being decoded is accumulated in anappropriate buffer. When the P_VOBs are completely input into thedecoder, the AOB is read from the optical disk and input to the decoder.When the AOB is input to the decoder, the STC, which is a referenceclock, is reset by the SCR in the leading pack, and the AOB is output atthe timing of the PTS in each pack header referring to the STC as in thecase of the VOB.

Information on the actual output timing of the P_VOBs is recorded inanother area of the optical disk (i.e., DLIST as a part of the PGCinformation). The information on the output timing is separatelysupplied to the decoder. Each P_VOB in the decoder is not outputsynchronously with the STC but at the display timing recorded in theDLIST. In other words, in reproducing the AOB, the PTS which is includedin the AOB is used to determine the display timing of the AOB; and inreproducing the P_VOB, the information which is separately recorded fromthe P_VOB is used to determine the display timing of the P_VOB.

The audio zone region and the DVD as a multimedia optical disk have beendescribed. Next, a reproduction apparatus in this example forreproducing a media having the above-described structure will bedescribed.

The basic structure of the reproduction apparatus in this example is thesame as those described in the first and second examples. As in thesecond example, a key for separately controlling audio data and videodata is provided in a remote controller for operating the DVD player oris provided on a front panel of the DVD player. With such a key, thevideo data can be skipped forward and backward or rewound to the startof the video data while continuously reproducing the audio data.

FIG. 61 is a block diagram illustrating an internal structure of a DVDplayer 90 in the third example. The DVD player 90 is different from theDVD player 70 shown in FIG. 8 in the structure of the AV decodersection, which will be described below.

In the third example, usable streams include an AOB as audio data, and aP_VOB as video data, and a VOB for menu or the like obtained bymultiplexing audio and video data. An AV decoder section 85 c includes aP_VOB system decoder 103, an AOB system decoder 104, and a VOB systemdecoder 108. The AV decoder section 85 c has a structure to operate thesystem decoders 103, 104 and 108 synchronously with and asynchronouslyfrom one another.

The P_VOB system decoder 103 receives a P_VOB stream and distinguishes astream ID and sub-stream ID in a header of each packet included in thestream, thereby classifying the data into a video packet, a PCI(highlight) packet, and a sub-picture packet.

The AOB system decoder 104 receives an AOB stream and classifies thedata on a packet header-by-packet header basis.

The VOB system decoder 108 receives a VOB stream and distinguishes astream ID and sub-stream ID in a header of each packet included in thestream, thereby classifying the data into an audio packet, a videopacket, a PCI (highlight) packet, and a sub-picture packet.

The AV decoder section 85 c still includes a highlight buffer 94 fortemporarily storing highlight information of a PCI packet from the P_VOBsystem decoder 103 and the VOB system decoder 108, a video buffer 96 fortemporarily storing a video packet from the P_VOB system decoder 103 andthe VOB system decoder 108, a sub-picture buffer 105 for temporarilystoring a sub-picture packet from the P_VOB system decoder 103 and theVOB system decoder 108, an audio buffer 99 for temporarily storing anaudio packet from the AOB system decoder 104 and the VOB system decoder108, a highlight decoder 95 for decoding the highlight data from thehighlight buffer 94 and outputting the decoded highlight data to thesystem control section 93, a video decoder 87 for decoding the videodata from the video buffer 96, a sub-picture decoder 98 for decoding thesub-picture data from the sub-picture buffer 105, an audio decoder 100for decoding the audio data from the audio buffer 99 and outputting thedecoded audio data as an audio output, a video synthesizer 101 forsynthesizing the decoding results of the video decoder 87 and thesub-picture decoder 98 into one piece of video data, and asynchronization adjusting section 102 for managing the synchronizationof the highlight decoder 95, the video decoder 87, the sub-picturedecoder 98 and the audio decoder 100.

The reproduction apparatus having the above-described structure operatesin, for example, the following manner. The operation up to the readingof the stream is the same as described in the first and second examplesand will not be described below.

FIGS. 62 through 66 are schematic flowcharts illustrating an operationfor reproducing the PGC information.

For starting the reproduction, the system control section 93 determineswhether or not the DVD player 90 is in a video-oriented reproductionmode, by a reproduction mode determination section. When it isdetermined that the DVD player 90 is in the video-oriented reproductionmode, the system control section 93 reads the video manager based on theinformation which is read from the volume file management region. Thesystem control section 93 refers to the PGC management information tablefor the video manager menu to calculate the recording address of the PGCfor the volume menu. The resultant PGC is reproduced and retainedinside. When the PGC for the volume menu is retained inside, the systemcontrol section 93 refers to the retained PGC information to calculatethe video object (VOB) to be reproduced and the recording address of theVOB on the optical disk. When the VOB to be reproduced is determined,the system control section 93 outputs a control signal to the mechanismcontrol section 83 and the signal processing section 84 so as toretrieve the determined VOB from the optical disk for reproduction. Whenthe system stream forming the VOB is input to the AV decoder section 85c, an instruction indicating “reproduce VOB” as a decode streaminstruction is given to the AV decoder section 85 a.

The VOB input to the AV decoder section 85 c is divided into streamsforming the VOB, i.e., an audio pack, video pack, sub-picture pack, andNV pack by the VOB system decoder 108, and the streams are respectivelyinput to the audio buffer 99, the video buffer 96, the sub-picturebuffer 105, and the highlight buffer 94. The highlight buffer 95 buffersonly the highlight information in the PCI packet in the NV pack. Datainput to each buffer is input to the audio decoder 100, the videodecoder 87, the sub-picture decoder 98 or the highlight decoder 95 to bedecoded. Audio data for menu is output from the audio decoder 100. Theoutputs from the video decoder 87 and the sub-picture decoder 98 aresynthesized by the video synthesizer 101 and output as video data. Theoutput from the highlight decoder 95 is read to the system controlsection 93 and the button information or the like of each menu is storedin the memory in the system control section 93.

Thus, a video menu from which the user can select the title to bereproduced (i.e., audio program) is displayed (see FIG. 40).

The user sees the menu and selects and confirms the title that he/she isinterested in by designating the item number in the menu using theremote controller. Then, the system control section 93 receives thedesignation of the item number in the menu from the remote controllerand refers to the button information of the highlight information of thePCI pack included in the VOB of the video menu which is beingreproduced, the VOB being stored in the memory, to execute a controlcommand corresponding to the designated number. The control command isPlayProgram #n or the like, and the title number to be reproduced isdesignated by “n”.

As an execution operation by the PlayProgram command, the system controlsection 93 refers to the title search pointer table, which is a part ofthe audio manager, to determine the audio title set (ATS) to which thedesignated title belongs to and the title number in the ATS. When theATS is confirmed, the system control section 93 outputs a control signalto the mechanism control section 83 and the signal processing section 84so as to reproduce the ATS management information of the confirmed titleset and sequentially retrieves ATS PGC information search pointer, whichis a part of the ATS management information, to determine the PGCinformation including the audio program to be reproduced.

When the PGC information is determined, the system control section 93outputs a control signal to the mechanism control section 83 and thesignal processing section 84 so as to reproduce the determined PGCinformation from the disk and retain the information in the insidebuffer memory for the PGC information.

When the PGC information is retained, the system control section 93reproduces the PGC information in accordance with the flowchart shown inFIG. 62. It is assumed that the audio program to be produced is alreadydetermined by the above-described menu command or direction designationusing the remote controller. The system control section 93 refers to theretained PGC information to first acquire the ASVU number of the firstaudio program information and compares the number with the ASVU numberpreviously reproduced. When the ASVU number is changed, the systemcontrol section 93 reads all the still picture data, i.e., P_VOBsincluded in the ASVU based on the ASVU general information correspondingto the ASVU number and inputs the number into the AV decoder section 85c. Simultaneously, an instruction indicating “reproduce P_VOB” is givento the AV decoder section 85 c as a decode stream instruction from thesystem control section 93. The AV decoder section 85 c separates theinput P_VOBs on a pack-by-pack basis or packet-by-packet basis by theP_VOB system decoder 92 and stores the P_VOBs in corresponding buffermemories.

At this point, the size of the video buffer 96 needs to be larger thanthe sum of the sizes of the P_VOBs of the ASVU. For any reproductionapparatus, a maximum value of the total data amount of the P_VOBsincluded in the ASVU is set in order to guarantee the reproduction. Thevideo buffer 96 in any reproduction apparatus needs to have a sizeaccommodating the maximum value. In this example, the maximum value of 2MByte. Since an I picture is 100 to 200 Kbyte, 10 to 20 I pictures canbe reproduced along with the audio information.

When all the P_VOBs forming the ASVU are completely input to thedecoder, the highlight decoder 95, the video decoder 87, and thesub-picture decoder 98 do not perform a decoding operation. In order tostore all the data regarding the corresponding ASVU into the buffersbefore the audio data is reproduced, the highlight buffer 94, the videobuffer 96, and the sub-picture buffer 105 need to have a greater buffercapacity than the buffer capacity specified by MPEG2 or DVD-Video.

When all the P_VOBs are completely stored in the corresponding buffers,the AV decoder section 85 c and the audio decoder 100 are set to be in adecodable state by the audio encoding mode in the ATS PGC informationsearch pointer 832 corresponding to the designated PGC information forpreparation of the reproduction of the audio data of the designated PGC.Then, the system control section 93 prepares for the display of thestill picture. The system control section 93 determines the ATS audiostill video reproduction information from the ATS_ASV_PBI start addressof the audio program information.

When the audio still video display mode of the audio program informationis Browsable, the first DLIST of the ATS audio still video reproductioninformation determines the first still picture to be reproduced. Whenthe audio still video display mode is SlideShow, the DLIST having theearliest display timing among a plurality of DLISTs of the ATS audiostill video reproduction information in the range of audio programs tobe reproduced is selected. When the DLIST is determined, the systemcontrol section 93 displays the still picture, i.e., the P_VOBdesignated by the ASV number of the DLIST. Specifically, the systemcontrol section 93 outputs-display control information of the stillpicture information to the synchronization adjusting section 102 in theAV decoder section 85 c. The display control information includes a waitperiod until the I picture of the P_VOB to be updated is designated andthe update thereof is displayed. When the display control section isinput, the synchronization adjusting section 102 instructs the videodecoder 87 to output the designated I picture at the designated timingin accordance with the display control information. Thus, the P_VOB isdisplayed. Unlike the AOB and VOB, the P_VOB is output at the displaytiming recorded in a separate area.

When the display of the P_VOB is started, the audio data designated bythe audio program is reproduced simultaneously. Simultaneously, the keyoperation by the user is accepted.

The reproduction of the audio data designated by the audio program isperformed as shown in FIG. 63. First, the cell number (Cn) to bereproduced is determined by the ATS program information table and theATS cell reproduction information table. Here, since this is the startof the operation, the cell number is 1. When the cell type of the cellto be reproduced is a silent cell, processing for reproducing a silentcell is performed. This requires only the effective silent periodcorresponding to the reproduction time period of the silent cell. Whenthe cell is not a silent cell, the cell is an audio cell. Accordingly,the reproduction of the audio cell shown in FIG. 65 is performed. Inorder to output the audio data from the leading end of the audio cell,the AOB to be reproduced and the recording address thereof aredetermined based on the audio cell reproduction information, and acontrol signal is output to the mechanical control section 83 and to asignal processing section 84. Thus, the reproduction of the determinedAOB is prepared. The AOB read from the optical disk is input to the AVdecoder section 85 c. Simultaneously, the system control section 93gives an instruction indicating “reproduce AOB” as a decode streaminstruction to the AV decoder section 85 c. The AOB is decoded into anaudio stream by the AOB system decoder 104 and input to the audio buffer99 and then to the audio decoder 100. Thus, the AOB is prepared to beoutput as audio data. Once the AOB is prepared, the STC, which is areference clock, of the synchronization adjusting section 102 is resetby the SCR of the leading pack of the AOB, and the audio data in the AOBis output at the timing of the PTS stored in the packet header. When theoutput of the AOB is started, highlight information and sub-pictureinformation for the leading I picture of the P_VOB and the menu itemsdisplayed in the state of overlapping with the leading I picture aredecoded and output. Although it is not guaranteed that all the packetsof the AOB include a PTS, the audio decoder outputs the audio data whilecomplementing the PTS.

When the audio still video display mode is Browsable while the audiodata is being output and the display timing of DLIST corresponding tothe P_VOB which is being displayed reaches the PTS of the audio datawhich is being reproduced, it is determined that the display time periodof the still picture has passed and thus the still picture of the nextDLIST is reproduced. When the audio still video display mode of theaudio program is SlideShow and the audio program number of the nextDLIST is not the same as the audio program number of the DLIST which isbeing reproduced, it is determined that there is no DLIST to bereproduced and thus the still picture displayed is continuouslydisplayed. When the next DLIST is the same as the audio program numberof the DLIST which is being reproduced, the still picture of the nextDLIST is reproduced when the display timing of the next DLIST reachesthe PTS of the audio data which is being reproduced.

FIG. 66 is a flowchart illustrating the reproduction of the second andlater still pictures. First, the termination transition mode of theDLIST of the still picture which is being displayed is acquired. Whenthe termination transition mode is “no transition”, the display isterminated. When the termination transition mode is not “no transition”,i.e., when the transition effect is designated, the still picture iserased by the designated transition. The designated transition is, forexample, fading, by which the color becomes gradually lighter. It shouldbe noted that the transition effect may be ignored or replaced withanother effect unless the reproduction apparatus has a capability ofperforming the designated effect.

When the still picture displayed is erased, the start section transitionmode of the DLIST of the next still picture is acquired. When thetransition mode is “no transition”, the next still picture isimmediately displayed. When the transition mode is not “no transition”,i.e., when the transition effect is designated, the next still pictureis displayed with an effect. Thus, the still pictures are switched. Atthis point, the highlight information and the sub-picture informationalready read in the buffer are decoded as well as the video informationincluded in the P_VOB.

The processing in response to the key operations by the user isperformed as shown in FIG. 64. When the key operation accompanies achange of the audio program, i.e., when the key operation is forNextProgram (reproduction of the next audio program), PrevProgram(reproduction of the previous audio program), reproduction of thedesignated audio program, reproduction of the audio program by a commandafter the menu is retrieved, or a change of the audio cell, the audiocell of the audio program to be reproduced is changed and processing forreproducing the audio cell is performed (FIG. 65).

When the key operation by the user is for a change of only the stillpicture, i.e., the key operation is for NextDLIST (display of the nextDLIST), PrevDLIST (display of the previous still picture), or display ofthe designated DLIST, the designated still picture is selected andprocessing for reproducing the still picture is performed only when theaudio still video display mode of the designated still picture isBrowsable (FIG. 66).

In response to other key operations, the designated operation isperformed without changing the audio output or still picture output.Such operations include display of the reproduction state and switchingof the time display mode. In order to reproduce another stream (VOB)such as retrieval of the menu, the audio output and still picturedisplay are terminated and the apparatus is switched to decode the VOB.

Thus, all the titles are reproduced and the operation is stopped. Inaccordance with specific setting of the DVD player or the DVD, only onetitle can be reproduced before the operation is stopped, or a menu canbe displayed after reproduction of one or more titles is completed.

Hereinafter, the control of the video decoder and video buffer performedby the synchronization adjusting section 102 will be additionallydescribed.

Since data of a still picture is already stored in the buffer memory,the display of the still picture is managed based on the position in thebuffer memory at which the still picture of the designated cell of thedesignated program is recorded or based on the ordinal number (i.e.,first, second, etc.) of the still picture with respect to the start.When the management is performed based on the position in the buffermemory, the data is sent to the video decoder 87 from the designatedaddress in the video buffer 96 and displayed by an instruction of thesynchronization adjusting section 102. When the management is performedbased on the ordinal number of the still picture, the data stored in thevideo buffer 96 from the leading end thereof is sent to the videodecoder 87 and the display is switched when the designated ordinalnumber is reached. When the still picture is switched, display effectscan be added by designating the transition mode. The time to switch thestill picture can be designated on a program-by-program basis before andafter the display of the still picture. However, in the case where thereproduction apparatus does not have a special effect display function,the still picture can simply be switched with the display effects beingignored.

In a synchronous mode (SlideShow), the audio data is decoded by theaudio decoder 100, and the still picture, highlight and sub-picture arereproduced in accordance with the “display timing”. The synchronizationadjusting section 102 compares the reference time of the system and the“display timing” from the system control section 93 and control thesynchronization.

In this case, switching of only the display by the user is prohibited.SlideShow is effectively used, for example, for displaying lyrics alongwith the music and displaying a still picture in a moving picture. Inthe asynchronous mode (Browsable), audio data is not synchronized withand reproduced separately from highlight data, sub-picture data andstill picture data. The highlight data, sub-picture data and stillpicture data are synchronized to one another, and the audio data iscontinuously reproduced in realtime based on the time information of thesystem. The still picture is switched in the asynchronous mode by theuser operation and the command. The user operation basically are, forexample, an operation of continuously reproducing audio programs whilefeeding display list (DLIST) forward, backward or to the leading end;and an operation of feeding both audio programs and display list (DLIST)simultaneously forward, backward or to the leading end. The command hassimilar functions. In this case, the “display timing” is considered asthe display continuation time period of the still picture. When theinteraction from the user is not generated during the time period of the“display timing”, a still picture is displayed based on the next DLIST.

Browsable is effectively used, for example, for displaying photos in aswitching manner while music is reproduced and displaying various typesof information including an explanation about the music and informationon the people involved in a switching manner.

The synchronous mode and the asynchronous mode are switched over inaccordance with the picture program reproduction control. The audiostill video display mode of the audio program information can bedesignated so that some of the audio programs included in the audiotitle are randomly selected and repeated a designated number of times orsuch audio programs are repeated a designated number of timesprohibiting repetition of the same program (shuffle mode).

The AV decoder section 85 c can have other structures.

As shown in FIG. 67, the system decoders for AOB, P_VOB and VOB can bereplaced with a single system decoder 109 having the functions of thesedecoders. Since the AOB is input at different timing from the P_VOB andVOB, a system decoder which is substantially the same as that specifiedby DVD-Video is usable except that the buffer memory capacities of thehighlight buffer 94, the video buffer 96 and the sub-picture buffer 105are increased and that a management mechanism for a still picture isadded to control of the video buffer 96. An AV decoder section 85 dshown in FIG. 67 operates in substantially the same manner as the AVdecoder section 85 c shown in FIG. 61.

As shown in FIG. 68, the P_VOB buffer 106 for P_VOB can be providedimmediately before the AV decoder section 85 d. The same type of AVdecoder section as used by DVD-Video is usable. All the P_VOB data to beread before the reproduction of the audio data is stored in the P_VOBbuffer 106. The P_VOB buffer 106 dynamically multiplexes the p_VOBscorresponding to the reproduction order with the audio stream and sendsthe resultant data to the AV decoder section 85 d. Accordingly, thesystem decoder 109 for AOB and P_VOB in the AV decoder section 85 d isrequired to have a processing speed which is slightly higher than thespeed specified by the DVD-Video standards. Streams need to be suppliedto the AV decoder section 85 d so that the audio buffer 99 does notunderflow.

In the third example, as described above, program reproductioninformation including the start time and reproduction time period ofeach piece of audio data based on the reproduction start time of theleading audio data in the MPEG2 stream is recorded in the managementregion as a part of the reproduction control information. Accordingly,an optical disk for realizing reproduction of high quality digital audiodata along with the video data in a restricted range of bit rates isprovided. Moreover, a certain interval between audio reproductions canbe maintained even in an inexpensive reproduction apparatus including novideo data reproduction function. This allows title creators to createdata easily.

Since a plurality of still pictures, sub-picture and menu can bedisplayed synchronously with or asynchronously from high quality audiodata, a wider variety of displays become available.

According to the present invention, reproduction order informationdefining the order of the video streams to be reproduced synchronouslywith an audio sequence is recorded on a recording medium. By changingthe contents of the reproduction order information, the contents of thevideo streams reproduced synchronously with the audio sequence caneasily be changed. This provides the title creators with the freedom ofcreating a variety of video streams for one audio sequence, and providesthe user with the freedom of selecting a desired video stream among aplurality of video streams offered for one audio sequence.

According to the present invention, video reproduction mode informationis recorded on the recording medium. Whether it is possible or not tochange the order of the video stream to be reproduced in synchronizationwith the audio sequence based on interaction from a user is adjusted bythe video reproduction mode information. The video reproduction modeinformation enables the switching of the reproductiontiming/reproduction time period of the video stream to be reproducedsynchronously with the audio sequence. Thus, the two different types ofvideo reproduction modes, i.e., “SlideShow” and “Browsable” can beoffered to the user.

According to the present invention, prior to the reproduction of theaudio sequence, a video stream to be reproduced synchronously with theaudio sequence is buffered in the buffer provided in the reproductionapparatus. By guaranteeing the range of the recording medium to read tothe buffer, reproduction by any reproduction apparatus is guaranteed. Asa result, title creators can easily assume the situation in which titlesare reproduced, which facilitates the production of the titles.Consequently, the high quality titles can be supplied at lower cost.

According to the present invention, a non-MPEG stream can be decoded byan MPEG2 decoder. Thus, the reproduction apparatus can be provided atlower cost.

Various other modifications will be apparent to and can be readily madeby those skilled in the art without departing from the scope and spiritof this invention. Accordingly, it is not intended that the scope of theclaims appended hereto be limited to the description as set forthherein, but rather that the claims be broadly construed.

What is claimed is:
 1. An optical disk comprising: an audio zone regionstoring a plurality of audio sequences and management information formanaging the reproduction of each of the plurality of audio sequences,wherein each of the plurality of audio sequences includes at least oneaudio object, the management information includes reproduction orderinformation indicating the reproduction order of the at least one audioobject included in each of the plurality of audio sequences, each of theat least one audio object includes at least one pack, each of the atleast one pack including audio data and first timing informationindicating an output timing of the audio data, the audio zone regionfurther stores at least one picture video object, each of the at leastone picture video object containing still picture data, the managementinformation further includes: still picture reproduction informationindicating at least one picture video object which is to be reproducedin connection with the reproduction of a corresponding one of theplurality of audio sequences, second timing information indicating anoutput timing of the at least one picture video object indicated by thestill picture reproduction information, and display mode informationindicating a display timing mode and a display order mode, wherein thedisplay timing mode is one of a first display timing mode in which theat least one picture video object is reproduced in synchronization withthe reproduction of the corresponding audio sequence and a seconddisplay timing mode in which the at least one picture video object isreproduced asynchronously from the reproduction of the correspondingaudio sequence, and the display order mode is one of a first displayorder mode in which the at least one picture video object is reproducedsequentially, and a second display order mode in which the at least onepicture video object is reproduced randomly while permitting overlap anda third display order mode in which the at least one picture videoobject is reproduced randomly while prohibiting overlap.
 2. Areproduction apparatus for reproducing information stored in the opticaldisk according to claim 1, the reproduction apparatus comprising: areading section for reading the at least one audio object, the at leastone picture video object and the management information from the opticaldisk; a reproduction section for reproducing the at least one audioobject and the at least one picture video object; and a control sectionfor controlling the reading section and the reproduction section,wherein the control section controls the reproduction section to updatethe display of the picture video object at the timing indicated by thesecond timing information, when the display timing mode indicated by thedisplay mode information is the first display timing mode, the controlsection controls the reproduction section to continue the display of thepicture video object during a time period indicated by the second timinginformation, when the display timing mode indicated by the display modeinformation is the second display timing mode, the control sectioncontrols the reproduction section to reproduce the at least one picturevideo object sequentially, when the display order mode indicated by thedisplay mode information is the first display order mode, the controlsection controls the reproduction section to reproduce the at least onepicture video object randomly while permitting overlap, when the displayorder mode indicated by the display mode information is the seconddisplay order mode, and the control section controls the reproductionsection to reproduce the at least one picture video object randomlywhile prohibiting overlap, when the display order mode indicated by thedisplay mode information is the third display order mode.